EP3437753B1 - Method for manufacturing a mechanical clinch joining component - Google Patents
Method for manufacturing a mechanical clinch joining component Download PDFInfo
- Publication number
- EP3437753B1 EP3437753B1 EP17774133.7A EP17774133A EP3437753B1 EP 3437753 B1 EP3437753 B1 EP 3437753B1 EP 17774133 A EP17774133 A EP 17774133A EP 3437753 B1 EP3437753 B1 EP 3437753B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- joining
- less
- ceq
- steel sheets
- mechanical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000005304 joining Methods 0.000 title claims description 157
- 238000000034 method Methods 0.000 title claims description 47
- 238000004519 manufacturing process Methods 0.000 title claims description 31
- 229910000831 Steel Inorganic materials 0.000 claims description 123
- 239000010959 steel Substances 0.000 claims description 123
- 238000010438 heat treatment Methods 0.000 claims description 25
- 239000000203 mixture Substances 0.000 claims description 15
- 229910052799 carbon Inorganic materials 0.000 claims description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 13
- 239000000470 constituent Substances 0.000 claims description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 8
- 229910052796 boron Inorganic materials 0.000 claims description 7
- 229910052804 chromium Inorganic materials 0.000 claims description 6
- 229910052748 manganese Inorganic materials 0.000 claims description 6
- 229910052758 niobium Inorganic materials 0.000 claims description 6
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 5
- 229910052750 molybdenum Inorganic materials 0.000 claims description 5
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 230000009466 transformation Effects 0.000 claims description 5
- 229910052720 vanadium Inorganic materials 0.000 claims description 5
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 19
- 230000000694 effects Effects 0.000 description 15
- 239000011651 chromium Substances 0.000 description 14
- 239000011572 manganese Substances 0.000 description 14
- 238000003825 pressing Methods 0.000 description 14
- 230000000171 quenching effect Effects 0.000 description 14
- 239000010936 titanium Substances 0.000 description 14
- 230000008569 process Effects 0.000 description 13
- 239000010949 copper Substances 0.000 description 12
- 239000010955 niobium Substances 0.000 description 11
- 238000012360 testing method Methods 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 238000011156 evaluation Methods 0.000 description 6
- 229910000797 Ultra-high-strength steel Inorganic materials 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 4
- 230000007547 defect Effects 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000010791 quenching Methods 0.000 description 4
- 230000002787 reinforcement Effects 0.000 description 4
- 238000005482 strain hardening Methods 0.000 description 4
- 229910052719 titanium Inorganic materials 0.000 description 4
- 238000003466 welding Methods 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000007731 hot pressing Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 3
- 229910052698 phosphorus Inorganic materials 0.000 description 3
- 238000005554 pickling Methods 0.000 description 3
- 238000007747 plating Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 3
- 229910001335 Galvanized steel Inorganic materials 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000010960 cold rolled steel Substances 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000008397 galvanized steel Substances 0.000 description 2
- 238000007429 general method Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 239000011574 phosphorus Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- 229910052726 zirconium Inorganic materials 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000000611 regression analysis Methods 0.000 description 1
- 238000004826 seaming Methods 0.000 description 1
- VSZWPYCFIRKVQL-UHFFFAOYSA-N selanylidenegallium;selenium Chemical compound [Se].[Se]=[Ga].[Se]=[Ga] VSZWPYCFIRKVQL-UHFFFAOYSA-N 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/20—Deep-drawing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/20—Deep-drawing
- B21D22/208—Deep-drawing by heating the blank or deep-drawing associated with heat treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D39/00—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
- B21D39/03—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of sheet metal otherwise than by folding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D39/00—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
- B21D39/03—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of sheet metal otherwise than by folding
- B21D39/031—Joining superposed plates by locally deforming without slitting or piercing
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/32—Ferrous alloys, e.g. steel alloys containing chromium with boron
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
Definitions
- the present invention relates to a method for manufacturing a mechanical clinched joint component, and more particularly, to a method for manufacturing a high-strength mechanical clinched joint component successfully without occurrence of a defect such as a crack.
- An ultra-high-strength steel sheet is increasingly used in a vehicle body frame for providing both collision safety and weight reduction of an automobile.
- an automobile steel component is reinforced by joining, using spot welding, a reinforcement member to a main member of the steel component to partly increase the thickness of the steel component.
- this method requires a spot welding process for joining after production of both the main member and the reinforcement member, thereby presents a problem of cost increase.
- mechanical clinch joining is known as a joining method of spot joining by cold working.
- This joining method is a kind of staking operation to join metal components together mechanically.
- Table 1 summarizes types of staking operation and features of the respective types. As illustrated in Table 1, there are several types of staking operation. Among these is mechanical clinch joining, which is a method in which two or more metal sheets are pressed at one time using a convex punch and a concave die.
- This mechanical clinch joining is characterized in that, as illustrated in Table 1, no pretreatment or auxiliary joining elements are required; that the joining process can be performed during press forming; and that application of mechanical clinch joining to a hot forming process further enables the joint portion to be quenched by cooling effect by the die.
- Patent Literature 1 describes performing of a staking operation called TOX® during pressing, which seems cold pressing.
- this joining method is intended for an outer side panel having a low matrix strength, and is therefore supposedly inapplicable to an ultra-high-strength staked component.
- Patent Literature 2 describes performing of press work using a press die at a lower temperature under a condition in which a burring portion of the bracket portion member unheated has been fit into a receiving hole of a beam body member at a high temperature at 850°C or above, thus to perform, at one time, forming and quenching of the beam body, and staking of the bracket portion with the beam body by bending or collapsing of the burring portion.
- this method requires a bracket portion preparation step to previously form the bracket portion member having a cylindrical flange-shaped burring portion fittable into the receiving hole of the beam body member. That is, production of a complex shape requires another step in addition to the pressing step, thereby increasing the cost. In addition, since use of an ultra-high-strength steel sheet is not taken into account, the heating and staking operation may cause a crack, or cause failure in providing sufficiently high peel strength.
- a component having ultra-high strength and sufficiently high peel strength in particular, a component produced using an ultra-high-strength steel sheet having a tensile strength of 1180 megapascal (MPa) or greater using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
- MPa megapascal
- the present invention has been made in view of the foregoing background, and it is an object of the present invention is to provide a method for manufacturing a mechanical clinched joint component having ultra-high strength and sufficiently high peel strength using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
- JP 2013-022628 A describes a method of manufacturing a metal junction body and a metal junction body.
- KR 2004 0017462 A describes forming a press metallic pattern for simultaneously clinching and forming plural panels.
- a mechanical clinched joint component produced by the method of the present invention which is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- a method for manufacturing the mechanical clinched joint component sequentially includes heating the two or more steel sheets to an Ac3 temperature or above, the steel sheets having a tensile strength of 1180 MPa or more; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) below and of equation (2) below: Ceq ⁇ 0.00209 ⁇ t + 0.000731 ⁇ T ⁇ 0.0365 ⁇ 0.200 Ceq ⁇ ⁇ 0.00071 ⁇ T + 0.993 where Ceq represents the carbon equivalent (mass%) of the steel sheets calculated by equation (3) below, t represents the bottom-dead-center holding time (second), and T represents the joining start temperature (°C).
- Ceq C + 1 / 6 ⁇ Mn + 1 / 24 ⁇ Si + 1 / 40 ⁇ Ni + 1 / 5 ⁇ Cr + 1 / 4 ⁇ Mo + 1 / 14 ⁇ V
- each of element names represents a content in mass% in the steel sheets, and represents zero if that element is not contained, and wherein the mechanical clinched joint component includes at least one joint portion
- Ac3 transformation point (°C) 910 - 203 ⁇ [C]0.5 - 15.2 ⁇ [Ni] + 44.7 ⁇ [Si] + 104 ⁇ [V] + 31.5 ⁇ [Mo] + 13.1 ⁇ [W] - 30 ⁇ [Mn] - 11 ⁇ [Cr] - 20 ⁇ [Cu] + 700 ⁇ [P] + 400 ⁇ [Al] + 400 [Ti], and hot press forming is also performed in the step of performing mechanical clinch joining
- the present inventors have carried out considerable research to solve the problem described above.
- cold forming was performed on steel sheets having a tensile strength from 270 to 1470 MPa and sheet thickness of 1.4 mm to join the steel sheets together crosswise using a die having attached thereto a mechanical clinching tool used in examples described later.
- the results confirm that, as illustrated in Table 2, a steel sheet tensile strength of 780 MPa or greater has caused a crack during joining, thereby causing failure in mechanical clinch joining.
- the present inventors have found that the relationships between the carbon equivalent Ceq of the steel sheets, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining need to satisfy equation (1) and equation (2) given later in the joining step after the heating step of heating the steel sheet to a certain temperature or higher.
- a mechanical clinched joint component produced by the present invention is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- the configuration described above can provide a mechanical clinched joint component having ultra-high strength and sufficiently high peel strength.
- the method for manufacturing the mechanical clinched joint component is characterized in sequentially including heating the two or more steel sheets to an Ac3 temperature or above; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) and of equation (2) given later.
- Such configuration can provide a method for manufacturing the mechanical clinched joint component as described above using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
- the two or more steel sheets are heated to an Ac3 temperature or above first.
- This heating process facilitates the joining process described later, and enables a joint component having a desired characteristic to be produced.
- the heating temperature is preferably [Ac3 temperature + 10]°C or higher. An excessively high temperature for this heating temperature results in a coarse microstructure, and thus may reduce ductility or bendability.
- the upper limit of the heating temperature is preferably [Ac3 temperature + 180]°C, and more preferably about [Ac3 temperature + 150]°C.
- the Ac3 temperature can be determined using the following equation described in " Leslie Tekkou Zairyougaku” (originally titled “The Physical Metallurgy of Steels,” Maruzen Co., Ltd., published on May 31, 1985, p.273 ).
- the expression [element name] represents the content in mass% of that element contained in the steel.
- the value for an element not contained can be calculated as zero.
- Ac 3 transformation point ° C 910 ⁇ 203 ⁇ C 0.5 ⁇ 15.2 ⁇ Ni + 44.7 ⁇ Si + 104 ⁇ V + 31.5 ⁇ Mo + 13.1 ⁇ W ⁇ 30 ⁇ Mn ⁇ 11 ⁇ Cr ⁇ 20 ⁇ Cu + 700 ⁇ P + 400 ⁇ Al + 400 Ti
- the heating duration at the heating temperature described above is preferably one minute or more. In addition, in view of limiting grain growth of austenite and the like, the heating duration is preferably 15 minutes or less.
- the temperature may be raised to the Ac3 transformation point at any rate. Examples of the method of heating include furnace heating, Joule heating, and induction heating.
- the present inventors have considered conditions for this joining step particularly to increase the peel strength of the joint portion of the joint component.
- the value CTS/L obtained by division of CTS by L is used as the peel strength. This allows peel strength to be evaluated regardless of the size of the joint portion.
- the value L corresponds to the circumference of this circular shape.
- joining conditions have also been considered to provide a component having a component hardness and the above peel strength of a certain predetermined value or greater, in particular, the peel strength CTS/L of 0.200 kN/mm or greater.
- manufacturing of a mechanical clinched joint component using different steel sheet compositions, different bottom-dead-center holding times, and different joining start temperatures as shown in examples described later has shown that joining conditions exist for forming a component having the component hardness and the peel strength each of a certain predetermined value or greater without occurrence of a crack.
- the peel strength CTS/L is expressed as equation (4) given below using the carbon equivalent Ceq, serving as an index of the steel sheet quenching property, the bottom-dead-center holding time t, and the joining start temperature T.
- the value Ceq (mass%) is a value calculated from equation (3) below defined in JIS G 0203, and the values a, b, and c are coefficients.
- the present inventors have manufactured mechanical clinched joint components using different steel sheet compositions, different bottom-dead-center holding times, and different joining start temperatures as described in examples described later, and performed experiments of determining peel strength of the components manufactured. To find out an equation for achieving a peel strength of 0.200 kN/mm or greater, multiple regression analysis has been performed on the experimental results to determine the values of the coefficients a, b, and c in equation (4) above, and equation (1) below has thus been obtained.
- Ceq C + 1 / 6 ⁇ Mn + 1 / 24 ⁇ Si + 1 / 40 ⁇ Ni + 1 / 5 ⁇ Cr + 1 / 4 ⁇ Mo + 1 / 14 ⁇ V
- Equation (2) below is given in view of the fact that the joining start temperature is affected by the steel sheet constituent composition, in particular, by Ceq among others. Equation (2) below has also been drawn by manufacturing mechanical clinched joint components using different steel sheet compositions and different joining start temperatures, and by performing experiments of determining peel strength of the components manufactured. Ceq ⁇ ⁇ 0.00071 ⁇ T + 0.993 where Ceq represents the carbon equivalent (mass%) of the steel sheets calculated by equation (3) above, and T represents the joining start temperature (°C).
- the two or more steel sheets used in mechanical clinch joining of this embodiment may have different constituent compositions, i.e., different Ceq values, between the steel sheets.
- the lowest value of Ceq is used in equation (1) and in equation (2).
- Performing joining under the conditions that satisfy equation (1) and equation (2) above enables all the conditions (A) to (D) to be satisfied. That is, a mechanical clinched joint component having (A) component strength of Hv ⁇ 360 and (B) peel strength of CTS/L ⁇ 0.200 kN/mm can be manufactured without adding a preliminary process or post-process and at a reduced cost.
- Forming the shape of a component by mechanical clinch joining serves similarly to forming the shape of a component by pressing, and may thus contribute to improvement in rigidity of the component.
- the joining start temperature is preferably 400°C or higher.
- the bottom-dead-center holding time preferably has a longer value in view of improvement in peel strength, but if productivity is of importance, or a multiple-step process described later is performed, the bottom-dead-center holding time for one joining operation is preferably 3 seconds or less.
- hot press forming is also performed in the step of performing mechanical clinch joining.
- the hot press forming may be performed under any conditions, and may be performed using a commonly used method.
- the temperature at the start of press forming i.e., at the time when the die reaches the position in contact with the steel sheet, is preferably about 400°C or higher.
- the method for manufacturing a joint component of this embodiment needs only to include the heating step and the joining step described above in this order.
- the joining step may be performed only once, or twice or more.
- a step, for example, of processing the steel sheets as described in the first step of the second aspect described below may be performed as other step than the joining step.
- This embodiment eliminates the need to perform other step than the heating and forming steps, thereby enabling a joint component to be manufactured at high productivity at a reduced cost.
- Specific aspects of the manufacturing method according to this embodiment in a case in which joining is performed simultaneously with hot press forming include, for example, a first aspect and a second aspect described below.
- the present invention is not limited to these aspects.
- examples described below are described in terms of spot joining for a circular clinched portion, other aspects including other shapes, such as spot joining of rectangular portion and linear joining along the longitudinal direction of the component, are also within the scope of the present invention.
- the forming process can be performed, for example, using a device illustrated in FIG. 1 .
- a steel sheet 1 heated and another steel sheet 2 heated serving as a reinforcement member are stacked together one on top of another, are placed on a support platform 3, and are air-cooled to a joining start temperature.
- a pressing punch 11 including therein a joining punch 6 is lowered to perform press forming and joining at one time.
- FIG. 1 illustrates a situation in which the bottom dead center has been reached.
- the steel sheets 1 and 2 are press-formed by the pressing die 8, the pad 9, and the pressing punch 11, and at the same time, are joined together by a joining die 4 included in the pad 9 and by the joining punch 6.
- the forming process can be performed, for example, as illustrated in FIGs. 2A to 2C .
- the steel sheets are heated, and thereafter, a first step illustrated in FIG. 2A , a second step illustrated in FIG. 2B , and a third step illustrated in FIG. 2C are performed consecutively.
- a first step illustrated in FIG. 2A a second step illustrated in FIG. 2B
- a third step illustrated in FIG. 2C are performed consecutively.
- the steel sheet 1 heated is placed on the support platform 3, and an excess length producing punch 10 is then lowered to produce an excess length in the steel sheet 1 that will form the outer wall of the component as illustrated in FIG. 2A .
- the other steel sheet 2 is placed over the steel sheet 1 having the excess length, and the joining punch 6 is then lowered to join together the steel sheets 1 and 2 at two points by the joining punch 6 and by the joining die 4 included in the pressing die 8 as illustrated in FIG. 2B .
- joint portions 12A and 12B are produced.
- a third step which is the last step, hot press forming and joining are performed at one time.
- the pressing punch 11 including therein the joining punch 6 is lowered to perform press forming as well as joining.
- FIG. 2C illustrates a situation in which the bottom dead center has been reached.
- the steel sheets 1 and 2 are press-formed by the pressing die 8, the pad 9, and the pressing punch 11, and at the same time, are joined together by the joining die 4 included in the pad 9 and by the joining punch 6 to form a joint portion 12C.
- This step enables the joint portions 12A and 12B to be formed on a component vertical wall portion 13.
- the steel sheet 1 and the other steel sheet 2 are applicable, for example, respectively as an outer component and an inner component.
- the joining step may be performed on a same portion twice or more as described in Example 2 described below.
- the constituents of the steel sheets for use in the joining described above are not particular limited.
- the two or more steel sheets may satisfy the conditions of constituent composition given below.
- Examples of usable type of steel sheet include hot-rolled steel sheets, cold-rolled steel sheets, plated steel sheets such as galvanized steel sheets produced by plating these steel sheets, and alloyed hot-dip galvanized steel sheets produced by further performing alloying. This method is applicable not only to joining of steel sheets, but also to joining of different materials (i.e., application of multi-material technology) such as a steel sheet and an aluminum sheet.
- constituent compositions of the steel sheets forming the component of this embodiment that is, the constituent compositions of the steel sheets for use in the joining may include the composition described below. Note that, as used in the description of constituent composition given below, the unit “%" means mass% unless otherwise indicated.
- the content of C is preferably 0.15% or more.
- the content of C is more preferably 0.17% or more, and is still more preferably 0.20% or more. Meanwhile, in view of weldability of the member produced, the content of C is preferably up to 0.4% or less, more preferably 0.30% or less, and still more preferably 0.26% or less.
- Silicon (Si) is an element effective in improving the quenching property of a hot-pressed steel sheet, and in stably ensuring the strength of a hot press-formed component.
- the content of Si is preferably 0.05% or more, and more preferably 0.15% or more.
- an excess content of Si impedes production of a milder steel sheet for hot pressing, and moreover, significantly raises the Ac3 temperature, thereby causing the ferrite component to remain at the heating stage in hot pressing. This makes it hard to achieve high strength.
- the content of Si is preferably 2% or less, more preferably 1.65% or less, and still more preferably 1.45% or less.
- Manganese (Mn) and chromium (Cr) are each an element useful for improving the quenching property of a steel sheet to produce a high-strength member. These elements may be used alone or in combination of two or more. From the viewpoint described above, at least one of Mn and Cr is contained preferably with a content of 1.0% or more in total, more preferably 1.5% or more in total, still more preferably 1.8% or more in total, and yet further preferably 2.0% or more in total. However, an excess content of any of these elements only results in saturation of the effect thereof, and thus results in a cost increase. Thus, in this embodiment, at least one of Mn and Cr is contained preferably with a content of 5.0% or less in total, more preferably 3.5% or less in total, and still more preferably 2.8% or less in total.
- the constituent composition may include the constituents described above, with the balance being iron and incidental impurities.
- the incidental impurities may include, for example, phosphorus (P), sulfur (S), and nitrogen (N) as described below.
- the content of P is preferably limited to 0.05% or less, more preferably to 0.045% or less, and still more preferably to 0.040% or less. Note that the content of P cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of P is greater than 0%.
- the content of S is preferably limited to 0.05% or less, more preferably to 0.045% or less, and still more preferably to 0.040% or less. Note that the content of S cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of S is greater than 0%.
- N Nitrogen fixes boron (B) as BN, thereby reducing the quenching property improvement effect.
- the content of N is preferably 0.01% or less, more preferably 0.008% or less, and still more preferably 0.006% or less. Note that the content of N cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of N is greater than 0%.
- containing of selective element(s) described below such as titanium (Ti) in a suitable amount can have effects such as facilitation of achievement of high strength. If at least one of Ti, B, aluminum (Al), molybdenum (Mo), copper (Cu), nickel (Ni), niobium (Nb), vanadium (V), and zirconium (Zr) is contained, these elements may be used alone or in combination of two or more. These elements will be described below.
- Titanium fixes nitrogen as TiN to cause boron to exist in a solid solution state, and is thus effective in providing good quenching property. If such effect of titanium is to be utilized, the content of Ti is preferably greater than 0%, more preferably 0.015% or more, and still more preferably 0.020% or more. Meanwhile, an excess content of Ti increases the strength of the steel sheets to be processed more than necessary, thereby decreasing the lives of cutting tool and punching die, and thus increasing the cost. Therefore, the content of Ti is preferably 0.10% or less, more preferably 0.06% or less, and still more preferably 0.04% or less.
- Boron is an element useful for improving the quenching property of a steel product to achieve high strength even using slow cooling. If such effect of boron is to be utilized, the content of B is preferably greater than 0%, more preferably 0.0003% or more, still more preferably 0.0015% or more, and yet further preferably 0.0020% or more. Meanwhile, an excess content of B results in excess generation of BN, thereby decreasing in toughness. Thus, the content of B is preferably 0.005% or less, more preferably 0.0040% or less, and still more preferably 0.0035% or less.
- Aluminum is an element used for deacidification. If this effect is to be utilized, the content of Al is preferably greater than 0%, and more preferably 0.01% or more. Meanwhile, a higher content of Al has a larger effect on raising the Ac3 temperature, thereby requiring a higher heating temperature in hot pressing, which reduces production efficiency. Thus, the content of Al is preferably 0.5% or less, more preferably 0.20% or less, still more preferably 0.10% or less, and yet further preferably 0.050% or less.
- Molybdenum is an element effective in improving the quenching property of a steel sheet. It is expected that containing of this element reduce variation in hardness of the formed products. If this effect of molybdenum is to be utilized, the content of Mo is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Mo only results in saturation of this effect, and thus results in a cost increase. Thus, the content of Mo is preferably 1% or less, more preferably 0.8% or less, and still more preferably 0.5% or less.
- Copper is an element effective in improving the quenching property, and is also useful for improving delayed-fracture resistance and oxidation resistance of a formed product. If this effect of copper is to be utilized, the content of Cu is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Cu may cause a surface flaw during steel sheet manufacturing. This will degrade pickling property, and thus reduce productivity. Thus, the content of Cu is preferably 0.5% or less, and more preferably 0.3% or less.
- Nickel is an element effective in improving the quenching property, and is also useful for improving delayed-fracture resistance and oxidation resistance of a formed product. If this effect of nickel is to be utilized, the content of Ni is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Ni may cause a surface flaw during steel sheet manufacturing. This will degrade pickling property, and thus reduce productivity. Thus, the content of Ni is preferably 0.5% or less, and more preferably 0.3% or less.
- Niobium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness.
- the content of Nb is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more.
- an excess content of Nb increases the strength of the steel sheets, thereby reducing the tool life in the blanking step including an operation such as cutting a steel sheet into a predetermined shape before hot press forming. This increases the cost.
- the content of Nb is preferably 0.10% or less, and more preferably 0.05% or less.
- Vanadium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness.
- the content of V is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more.
- an excess content of V increases the strength of the steel sheets similarly to the case of Nb, thereby reducing the tool life in the blanking step. This increases the cost.
- the content of V is preferably 0.10% or less, and more preferably 0.05% or less.
- Zirconium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness.
- the content of Zr is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more.
- an excess content of Zr increases the strength of the steel sheets similarly to the cases of Nb and V, thereby reducing the tool life in the blanking step. This increases the cost.
- the content of Zr is preferably 0.10% or less, and more preferably 0.05% or less.
- the method for manufacturing the steel sheets are not limited either. It is sufficient to perform, using general methods, casting, heating, and hot rolling, and pickling followed by cold rolling as needed, and furthermore, annealing as needed.
- the hot-rolled steel sheet or cold-rolled steel sheet produced may be plated, as needed, using plating such as zinc-containing plating using a general method, and then further be alloyed as needed.
- the mechanical clinched joint component produced by the method of the present invention is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- the method for manufacturing the mechanical clinched joint component sequentially includes heating the two or more steel sheets to an Ac3 temperature or above; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) below and of equation (2) below: Ceq ⁇ 0.00209 ⁇ t + 0.000731 ⁇ T ⁇ 0.0365 ⁇ 0.200 Ceq ⁇ ⁇ 0.00071 ⁇ T + 0.993 where Ceq represents the carbon equivalent (mass%) of the steel sheets calculated by equation (3) below, t represents the bottom-dead-center holding time (second), and T represents the joining start temperature (°C).
- Ceq C + 1 / 6 ⁇ Mn + 1 / 24 ⁇ Si + 1 / 40 ⁇ Ni + 1 / 5 ⁇ Cr + 1 / 4 ⁇ Mo + 1 / 14 ⁇ V
- each of element names represents a content in mass% in the steel sheets, and represents zero if that element is not contained, and wherein the mechanical clinched joint component includes at least one joint portion
- Ac3 transformation point (°C) 910 - 203 ⁇ [C]0.5 - 15.2 ⁇ [Ni] + 44.7 ⁇ [Si] + 104 ⁇ [V] + 31.5 ⁇ [Mo] + 13.1 ⁇ [W] - 30 ⁇ [Mn] - 11 ⁇ [Cr] - 20 ⁇ [Cu] + 700 ⁇ [P] + 400 ⁇ [Al] + 400 [Ti], and hot press forming is also performed in the step of performing mechanical clinch joining.
- the two or more steel sheets used in the method for manufacturing the mechanical clinched joint component may each have a constituent composition in mass% satisfying:
- the method for manufacturing the mechanical clinched joint component may perform the step of performing mechanical clinch joining a plurality of times.
- a steel sheet A and a steel sheet B having constituent compositions illustrated in Table 3 were each used to prepare two specimens having a dimension of 150 mm ⁇ 50 mm ⁇ sheet thickness 1.4 mm, and each pair of the two test specimens was mechanically clinched together using the tool illustrated in FIG. 3 .
- the steel sheet 1 and the other steel sheet 2 heated at 930°C for 4 minutes were stacked together, crosswise, one on top of another, and were placed on the support platform 3 between the joining punch 6 included in the joining punch holder 7 and the joining die 4 included in the joining die holder 5. After air cooling to the joining start temperature described below, the joining die 4 was lowered to perform mechanical clinch joining under the conditions listed below, and test specimens representing the component were thus produced.
- the hardness and peel strength of the test specimens produced were determined as follows.
- Vickers hardness Hv was determined at three points per steel sheet under a load condition of 1 kgf in a portion other than the joint portion, i.e., in a holder portion of the component, at a location of 1/4 sheet thickness of each steel sheet that constitute the component. The results of the three points were averaged for each steel sheet, and the lowest average value in the steel sheets was used as the hardness of that component. Evaluation was made against the following criteria.
- the cross tensile strength CTS (kN) of each test specimen was measured according to JIS Z 3137. This CTS value was divided by the circumference L (mm) of the joint portion to calculate the cross tensile strength per unit peripheral length CTS/L (kN/mm) of the joint portion as the peel strength. A peel strength corresponding to this CTS/L value of 0.200 kN/mm or greater was classified as high.
- FIGs. 4A and 4B are diagrams illustrating cross sections of the die used and of the joint component produced. As illustrated in FIG. 4B , the joint diameter d of the joint component was measured, and then a value of d/D was also calculated by dividing this joint diameter d by the die diameter D illustrated in FIG. 4A . A smaller d/D value indicates stronger joining, and the value of d/D is preferably 1.029 or less.
- Table 4 shows the following results for the case of the steel sheet A.
- Specimens Nos. 1 to 8 are those of examples of performing mechanical clinch joining so that the carbon equivalent Ceq of the steel sheets used, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining satisfy relationships of predetermined equation (1) and equation (2).
- joining was performed successfully without occurrence of a crack, and the component produced had a high hardness Hv corresponding to 1180 MPa or greater, and a peel strength CTS/L of 0.200 kN/mm or greater.
- a bottom-dead-center holding time of 10 seconds resulted in satisfactory hardness.
- a combination of a joining start temperature of 800°C and a bottom-dead-center holding time of 10 seconds further resulted in sufficiently high peel strength.
- specimen No. 9 had a joining start temperature that did not satisfy equation (2), thereby caused a soft phase to segregate. Therefore, even though no cracks occurred, the hardness was low, and the peel strength was also low.
- Table 5 shows the following results for the case of the steel sheet B.
- Specimens Nos. 1 to 12 are those of examples of performing mechanical clinch joining so that the carbon equivalent Ceq of the steel sheets used, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining satisfy relationships of predetermined equation (1) and equation (2).
- joining was performed successfully without occurrence of a crack, and the component produced had a high hardness Hv corresponding to 1180 MPa or greater, and a peel strength CTS/L of 0.200 kN/mm or greater.
- a joining start temperature of 500°C or higher achieved both Hv ⁇ 450 and CTS/L ⁇ 0.200kN/mm even without holding at the bottom dead center.
- steel sheets can be joined together using a joining start temperature from 500 to 600°C, and in addition, the bottom-dead-center holding time can be reduced or omitted. This enables joining in a multiple-step process, and joining to a vertical wall portion such as one illustrated in FIGs. 2A to 2C is also possible.
- FIG. 6 drawn based on the results of Table 4 and Table 5 above shows that the left-side values of equation (1) and CTS/L values almost match.
- Table 6 shows that performing a higher number of the joining operations increases the peel strength CTS/L. This may be because, despite the bottom-dead-center holding time being zero, pressing a same portion consecutively increases the number of contacts between the steel sheet and the tool to increase the total contact time therebetween, thereby decreasing the d/D value.
- the present invention has a wide range of industrial applicability in technical fields relating to mechanical clinch joining.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
- Heat Treatment Of Articles (AREA)
- Insertion Pins And Rivets (AREA)
Description
- The present invention relates to a method for manufacturing a mechanical clinched joint component, and more particularly, to a method for manufacturing a high-strength mechanical clinched joint component successfully without occurrence of a defect such as a crack.
- An ultra-high-strength steel sheet is increasingly used in a vehicle body frame for providing both collision safety and weight reduction of an automobile. To limit the degree of deformation to a certain level upon an impact of collision, an automobile steel component is reinforced by joining, using spot welding, a reinforcement member to a main member of the steel component to partly increase the thickness of the steel component. However, this method requires a spot welding process for joining after production of both the main member and the reinforcement member, thereby presents a problem of cost increase.
- Meanwhile, as an alternative to spot welding described above, a joining method called mechanical clinch joining is known as a joining method of spot joining by cold working. This joining method is a kind of staking operation to join metal components together mechanically. Table 1 summarizes types of staking operation and features of the respective types. As illustrated in Table 1, there are several types of staking operation. Among these is mechanical clinch joining, which is a method in which two or more metal sheets are pressed at one time using a convex punch and a concave die. This mechanical clinch joining is characterized in that, as illustrated in Table 1, no pretreatment or auxiliary joining elements are required; that the joining process can be performed during press forming; and that application of mechanical clinch joining to a hot forming process further enables the joint portion to be quenched by cooling effect by the die.
- This mechanical clinch joining can reduce cost and increase productivity as compared to spot welding. For example,
Patent Literature 1 describes performing of a staking operation called TOX® during pressing, which seems cold pressing. However, this joining method is intended for an outer side panel having a low matrix strength, and is therefore supposedly inapplicable to an ultra-high-strength staked component.[Table 1] STAKING OPERATION JOINING METHOD MECHANICAL CLINCHING SELF-PIERCING RIVET HOLE + BURRING LOCK SEAMING JOINING PERFORMED DURING PARTS FORMING POSSIBLE POSSIBLE POSSIBLE NOT POSSIBLE PRETREATMENT NOT REQUIRED NOT REQUIRED HOLE PROCESSING REQUIRED NOT REQUIRED AUXILIARY JOINING ELEMENT NOT REQUIRED RIVET REQUIRED NOT REQUIRED ADHESIVE REQUIRED QUENCHING BY DIE COOLING IN HOT FORMING POSSIBLE NOT POSSIBLE POSSIBLE POSSIBLE JOIN AT PART EDGES NOT POSSIBLE NOT POSSIBLE NOT POSSIBLE POSSIBLE JOIN TO PART SURFACE POSSIBLE POSSIBLE POSSIBLE NOT POSSIBLE - Mechanical clinch joining by cold working as described above presents a problem in that use of a steel sheet having high strength may cause a crack during joining, and may thus prevent production of a high-strength steel component. On the other hand,
Patent Literature 2 describes performing of press work using a press die at a lower temperature under a condition in which a burring portion of the bracket portion member unheated has been fit into a receiving hole of a beam body member at a high temperature at 850°C or above, thus to perform, at one time, forming and quenching of the beam body, and staking of the bracket portion with the beam body by bending or collapsing of the burring portion. - However, this method requires a bracket portion preparation step to previously form the bracket portion member having a cylindrical flange-shaped burring portion fittable into the receiving hole of the beam body member. That is, production of a complex shape requires another step in addition to the pressing step, thereby increasing the cost. In addition, since use of an ultra-high-strength steel sheet is not taken into account, the heating and staking operation may cause a crack, or cause failure in providing sufficiently high peel strength.
- Therefore, there is a need to manufacture a component having ultra-high strength and sufficiently high peel strength, in particular, a component produced using an ultra-high-strength steel sheet having a tensile strength of 1180 megapascal (MPa) or greater using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
- The present invention has been made in view of the foregoing background, and it is an object of the present invention is to provide a method for manufacturing a mechanical clinched joint component having ultra-high strength and sufficiently high peel strength using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
JP 2013-022628 A KR 2004 0017462 A -
- Patent Literature 1:
WO 2013/008515 A - Patent Literature 2:
JP 2006-321405 A - Herein described is a mechanical clinched joint component produced by the method of the present invention, which is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- According to the present invention, a method for manufacturing the mechanical clinched joint component sequentially includes heating the two or more steel sheets to an Ac3 temperature or above, the steel sheets having a tensile strength of 1180 MPa or more; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) below and of equation (2) below:
-
-
FIG. 1 is a schematic diagram illustrating one aspect of the present invention. -
FIGs. 2A to 2C are schematic diagrams illustrating another aspect of the present invention. -
FIG. 3 is a diagram illustrating a die having a mechanical clinching tool attached thereto, used in production of test specimens in examples. -
FIGs. 4A and 4B are diagrams for describing calculation of the ratio d/D. -
FIGs. 5A to 5C are observation images of a cross section of the No. 5 component in one of examples.FIG. 5A is an image of the entire cross section of the component.FIG. 5B is an image of a portion of the cross section of the component.FIG. 5C is an enlarged image of the ellipse portion ofFIG. 5B . -
FIG. 6 is a chart illustrating the relationship between the left-side value of equation (1) and the CTS/L value. - The present inventors have carried out considerable research to solve the problem described above. First, to newly investigate the tensile strength limit that causes a crack during joining by cold working, cold forming was performed on steel sheets having a tensile strength from 270 to 1470 MPa and sheet thickness of 1.4 mm to join the steel sheets together crosswise using a die having attached thereto a mechanical clinching tool used in examples described later. The results confirm that, as illustrated in Table 2, a steel sheet tensile strength of 780 MPa or greater has caused a crack during joining, thereby causing failure in mechanical clinch joining. As user herein, the term "mechanical clinch joining" may also be referred to as "joining," and the term "mechanical clinch joining" may also be referred to as "joint component."
[Table 2] STEEL SHEET TENSILE STRENGTH (MPa) JOINING 270 OK 440 OK 590 OK 780 CRACKED 980 CRACKED 1180 CRACKED 1470 CRACKED - As described above, the present inventors have carried out considerable research for a method of performing mechanical clinch joining successfully on the assumption that a steel sheet having a tensile strength of 1180 MPa or greater, i.e., an ultra-high-strength steel sheet that is certain to initiate a crack during joining by cold working in view of the results of Table 2 shown above, is used as an ultra-high-strength steel sheet in high demand in recent years. In more detail, considerable researches were carried out to satisfy all the following conditions (A) to (D).
- (A) The component exhibits ultra-high strength. Specifically, the component exhibits, as its hardness, a Vickers hardness of 360 Hv or greater, i.e., a tensile strength of 1180 MPa or greater; preferably, a Vickers hardness of 450 Hv or greater, i.e., a tensile strength of 1470 MPa or greater.
- (B) The component has high peel strength. Specifically, the component has a cross tensile strength per unit peripheral length of the joint portion determined using a method described later herein, i.e., peel strength, of 0.200 kN/mm or greater.
- (C) The component can be manufactured by joining without occurrence of a crack.
- (D) No preliminary process before the press work or post-process after the press work is required, and thus a component can be manufactured at a reduced cost.
- In the present invention, the present inventors have found that the relationships between the carbon equivalent Ceq of the steel sheets, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining need to satisfy equation (1) and equation (2) given later in the joining step after the heating step of heating the steel sheet to a certain temperature or higher.
- That is, a mechanical clinched joint component produced by the present invention is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- The configuration described above can provide a mechanical clinched joint component having ultra-high strength and sufficiently high peel strength.
- According to the present invention, the method for manufacturing the mechanical clinched joint component is characterized in sequentially including heating the two or more steel sheets to an Ac3 temperature or above; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) and of equation (2) given later.
- Such configuration can provide a method for manufacturing the mechanical clinched joint component as described above using mechanical clinch joining successfully without occurrence of a defect such as a crack without adding an extra step other than the mechanical clinch joining step.
- Each step of this embodiment will be described below in detail.
- In this embodiment, to perform the joining process described above, the two or more steel sheets are heated to an Ac3 temperature or above first. This heating process facilitates the joining process described later, and enables a joint component having a desired characteristic to be produced. The heating temperature is preferably [Ac3 temperature + 10]°C or higher. An excessively high temperature for this heating temperature results in a coarse microstructure, and thus may reduce ductility or bendability. Thus, the upper limit of the heating temperature is preferably [Ac3 temperature + 180]°C, and more preferably about [Ac3 temperature + 150]°C.
- The Ac3 temperature can be determined using the following equation described in "Leslie Tekkou Zairyougaku" (originally titled "The Physical Metallurgy of Steels," Maruzen Co., Ltd., published on May 31, 1985, p.273). In the following equation, the expression [element name] represents the content in mass% of that element contained in the steel. In the following equation, the value for an element not contained can be calculated as zero.
- The heating duration at the heating temperature described above is preferably one minute or more. In addition, in view of limiting grain growth of austenite and the like, the heating duration is preferably 15 minutes or less. The temperature may be raised to the Ac3 transformation point at any rate. Examples of the method of heating include furnace heating, Joule heating, and induction heating.
- The present inventors have considered conditions for this joining step particularly to increase the peel strength of the joint portion of the joint component. First, in this embodiment, due to the dependence of the cross tensile strength CTS on the length L of the joint portion, the value CTS/L obtained by division of CTS by L is used as the peel strength. This allows peel strength to be evaluated regardless of the size of the joint portion. In examples described later which use circular joint portions, the value L corresponds to the circumference of this circular shape.
- In this embodiment, joining conditions have also been considered to provide a component having a component hardness and the above peel strength of a certain predetermined value or greater, in particular, the peel strength CTS/L of 0.200 kN/mm or greater. Specifically, manufacturing of a mechanical clinched joint component using different steel sheet compositions, different bottom-dead-center holding times, and different joining start temperatures as shown in examples described later has shown that joining conditions exist for forming a component having the component hardness and the peel strength each of a certain predetermined value or greater without occurrence of a crack.
- Further consideration has been made to find these joining conditions. First, considering that the peel strength seems to be affected after stamping, that is, by the hardness of the matrix of the component, that the hardness of the matrix is affected by the steel sheet quenching property, the quenching start temperature, and the bottom-dead-center holding time t, and that the quenching start temperature corresponds to the joining start temperature T in this embodiment, the peel strength CTS/L is expressed as equation (4) given below using the carbon equivalent Ceq, serving as an index of the steel sheet quenching property, the bottom-dead-center holding time t, and the joining start temperature T. In equation (4) below, the value Ceq (mass%) is a value calculated from equation (3) below defined in JIS G 0203, and the values a, b, and c are coefficients.
- The present inventors have manufactured mechanical clinched joint components using different steel sheet compositions, different bottom-dead-center holding times, and different joining start temperatures as described in examples described later, and performed experiments of determining peel strength of the components manufactured. To find out an equation for achieving a peel strength of 0.200 kN/mm or greater, multiple regression analysis has been performed on the experimental results to determine the values of the coefficients a, b, and c in equation (4) above, and equation (1) below has thus been obtained.
- It is likely that satisfaction of equation (1) above reduces a ratio d/D of the joint diameter d of the product with respect to the die diameter D, thereby enabling the peel strength to be improved.
- In this embodiment, satisfaction of equation (2) below is further required. Equation (2) below is given in view of the fact that the joining start temperature is affected by the steel sheet constituent composition, in particular, by Ceq among others. Equation (2) below has also been drawn by manufacturing mechanical clinched joint components using different steel sheet compositions and different joining start temperatures, and by performing experiments of determining peel strength of the components manufactured.
- The two or more steel sheets used in mechanical clinch joining of this embodiment may have different constituent compositions, i.e., different Ceq values, between the steel sheets. In such case, the lowest value of Ceq is used in equation (1) and in equation (2).
- Performing joining under the conditions that satisfy equation (1) and equation (2) above enables all the conditions (A) to (D) to be satisfied. That is, a mechanical clinched joint component having (A) component strength of Hv ≥ 360 and (B) peel strength of CTS/L ≥ 0.200 kN/mm can be manufactured without adding a preliminary process or post-process and at a reduced cost. Forming the shape of a component by mechanical clinch joining serves similarly to forming the shape of a component by pressing, and may thus contribute to improvement in rigidity of the component.
- In view of limiting an increase in forming load and reduction in formability, the joining start temperature is preferably 400°C or higher. The bottom-dead-center holding time preferably has a longer value in view of improvement in peel strength, but if productivity is of importance, or a multiple-step process described later is performed, the bottom-dead-center holding time for one joining operation is preferably 3 seconds or less.
- According to the present invention, hot press forming is also performed in the step of performing mechanical clinch joining. The hot press forming may be performed under any conditions, and may be performed using a commonly used method. To perform hot press forming successfully, the temperature at the start of press forming, i.e., at the time when the die reaches the position in contact with the steel sheet, is preferably about 400°C or higher.
- The method for manufacturing a joint component of this embodiment needs only to include the heating step and the joining step described above in this order. The joining step may be performed only once, or twice or more. In addition, during a time period from heating to completion of forming of the steel sheets, a step, for example, of processing the steel sheets as described in the first step of the second aspect described below may be performed as other step than the joining step. This embodiment eliminates the need to perform other step than the heating and forming steps, thereby enabling a joint component to be manufactured at high productivity at a reduced cost.
- Specific aspects of the manufacturing method according to this embodiment in a case in which joining is performed simultaneously with hot press forming include, for example, a first aspect and a second aspect described below. However, the present invention is not limited to these aspects. Although examples described below are described in terms of spot joining for a circular clinched portion, other aspects including other shapes, such as spot joining of rectangular portion and linear joining along the longitudinal direction of the component, are also within the scope of the present invention.
- Description is herein given with reference to the drawings, in which the reference symbols have meanings as follows: 1 steel sheet, 2 another steel sheet or reinforcement member steel sheet, 3 support platform, 4 joining die, 5 joining die holder, 6 joining punch, 7 joining punch holder, 8 pressing die, 9 pad, 10 excess length producing punch, 11 pressing punch, 12A, 12B, 12C joint portion, and 13 component vertical wall portion.
- In a first aspect, the forming process can be performed, for example, using a device illustrated in
FIG. 1 . In more detail, asteel sheet 1 heated and anothersteel sheet 2 heated serving as a reinforcement member are stacked together one on top of another, are placed on asupport platform 3, and are air-cooled to a joining start temperature. Apressing punch 11 including therein a joiningpunch 6 is lowered to perform press forming and joining at one time.FIG. 1 illustrates a situation in which the bottom dead center has been reached. In this first aspect, as illustrated inFIG. 1 , thesteel sheets pressing die 8, thepad 9, and thepressing punch 11, and at the same time, are joined together by a joiningdie 4 included in thepad 9 and by the joiningpunch 6. - In a second aspect, the forming process can be performed, for example, as illustrated in
FIGs. 2A to 2C . As illustrated inFIGs. 2A to 2C , the steel sheets are heated, and thereafter, a first step illustrated inFIG. 2A , a second step illustrated inFIG. 2B , and a third step illustrated inFIG. 2C are performed consecutively. Each of these steps will now be described. First, at the first step, thesteel sheet 1 heated is placed on thesupport platform 3, and an excesslength producing punch 10 is then lowered to produce an excess length in thesteel sheet 1 that will form the outer wall of the component as illustrated inFIG. 2A . Next, at the second step, theother steel sheet 2 is placed over thesteel sheet 1 having the excess length, and the joiningpunch 6 is then lowered to join together thesteel sheets punch 6 and by the joiningdie 4 included in thepressing die 8 as illustrated inFIG. 2B . Thus,joint portions - Then, at a third step, which is the last step, hot press forming and joining are performed at one time. In more detail, the
pressing punch 11 including therein the joiningpunch 6 is lowered to perform press forming as well as joining.FIG. 2C illustrates a situation in which the bottom dead center has been reached. In this third step, as illustrated inFIG. 2C , thesteel sheets pressing die 8, thepad 9, and thepressing punch 11, and at the same time, are joined together by the joiningdie 4 included in thepad 9 and by the joiningpunch 6 to form ajoint portion 12C. This step enables thejoint portions vertical wall portion 13. - In a case of an automobile steel component, the
steel sheet 1 and theother steel sheet 2 are applicable, for example, respectively as an outer component and an inner component. Although the foregoing aspects does not mention, the joining step may be performed on a same portion twice or more as described in Example 2 described below. - The constituents of the steel sheets for use in the joining described above are not particular limited. For example, the two or more steel sheets may satisfy the conditions of constituent composition given below. Examples of usable type of steel sheet include hot-rolled steel sheets, cold-rolled steel sheets, plated steel sheets such as galvanized steel sheets produced by plating these steel sheets, and alloyed hot-dip galvanized steel sheets produced by further performing alloying. This method is applicable not only to joining of steel sheets, but also to joining of different materials (i.e., application of multi-material technology) such as a steel sheet and an aluminum sheet.
- The constituent compositions of the steel sheets forming the component of this embodiment, that is, the constituent compositions of the steel sheets for use in the joining may include the composition described below. Note that, as used in the description of constituent composition given below, the unit "%" means mass% unless otherwise indicated.
- To readily achieve a component hardness of 360 Hv or greater, the content of C is preferably 0.15% or more. The content of C is more preferably 0.17% or more, and is still more preferably 0.20% or more. Meanwhile, in view of weldability of the member produced, the content of C is preferably up to 0.4% or less, more preferably 0.30% or less, and still more preferably 0.26% or less.
- Silicon (Si) is an element effective in improving the quenching property of a hot-pressed steel sheet, and in stably ensuring the strength of a hot press-formed component. From this viewpoint, the content of Si is preferably 0.05% or more, and more preferably 0.15% or more. However, an excess content of Si impedes production of a milder steel sheet for hot pressing, and moreover, significantly raises the Ac3 temperature, thereby causing the ferrite component to remain at the heating stage in hot pressing. This makes it hard to achieve high strength. Thus, the content of Si is preferably 2% or less, more preferably 1.65% or less, and still more preferably 1.45% or less.
- Manganese (Mn) and chromium (Cr) are each an element useful for improving the quenching property of a steel sheet to produce a high-strength member. These elements may be used alone or in combination of two or more. From the viewpoint described above, at least one of Mn and Cr is contained preferably with a content of 1.0% or more in total, more preferably 1.5% or more in total, still more preferably 1.8% or more in total, and yet further preferably 2.0% or more in total. However, an excess content of any of these elements only results in saturation of the effect thereof, and thus results in a cost increase. Thus, in this embodiment, at least one of Mn and Cr is contained preferably with a content of 5.0% or less in total, more preferably 3.5% or less in total, and still more preferably 2.8% or less in total.
- The constituent composition may include the constituents described above, with the balance being iron and incidental impurities. The incidental impurities may include, for example, phosphorus (P), sulfur (S), and nitrogen (N) as described below.
- Since phosphorus reduces ductility, the content of P is preferably limited to 0.05% or less, more preferably to 0.045% or less, and still more preferably to 0.040% or less. Note that the content of P cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of P is greater than 0%.
- Sulfur also reduces ductility similarly to P, the content of S is preferably limited to 0.05% or less, more preferably to 0.045% or less, and still more preferably to 0.040% or less. Note that the content of S cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of S is greater than 0%.
- Nitrogen fixes boron (B) as BN, thereby reducing the quenching property improvement effect. In addition, nitrogen forms coarse Ti-containing segregation such as TiN segregation, which may act as a starting point of fracture, and reduce the ductility of the steel sheets. Thus, the content of N is preferably 0.01% or less, more preferably 0.008% or less, and still more preferably 0.006% or less. Note that the content of N cannot be reduced to 0% for manufacturing reasons, and thus, the lower limit of the content of N is greater than 0%.
- In addition to the elements described above, containing of selective element(s) described below such as titanium (Ti) in a suitable amount can have effects such as facilitation of achievement of high strength. If at least one of Ti, B, aluminum (Al), molybdenum (Mo), copper (Cu), nickel (Ni), niobium (Nb), vanadium (V), and zirconium (Zr) is contained, these elements may be used alone or in combination of two or more. These elements will be described below.
- Titanium fixes nitrogen as TiN to cause boron to exist in a solid solution state, and is thus effective in providing good quenching property. If such effect of titanium is to be utilized, the content of Ti is preferably greater than 0%, more preferably 0.015% or more, and still more preferably 0.020% or more. Meanwhile, an excess content of Ti increases the strength of the steel sheets to be processed more than necessary, thereby decreasing the lives of cutting tool and punching die, and thus increasing the cost. Therefore, the content of Ti is preferably 0.10% or less, more preferably 0.06% or less, and still more preferably 0.04% or less.
- Boron is an element useful for improving the quenching property of a steel product to achieve high strength even using slow cooling. If such effect of boron is to be utilized, the content of B is preferably greater than 0%, more preferably 0.0003% or more, still more preferably 0.0015% or more, and yet further preferably 0.0020% or more. Meanwhile, an excess content of B results in excess generation of BN, thereby decreasing in toughness. Thus, the content of B is preferably 0.005% or less, more preferably 0.0040% or less, and still more preferably 0.0035% or less.
- Aluminum is an element used for deacidification. If this effect is to be utilized, the content of Al is preferably greater than 0%, and more preferably 0.01% or more. Meanwhile, a higher content of Al has a larger effect on raising the Ac3 temperature, thereby requiring a higher heating temperature in hot pressing, which reduces production efficiency. Thus, the content of Al is preferably 0.5% or less, more preferably 0.20% or less, still more preferably 0.10% or less, and yet further preferably 0.050% or less.
- Molybdenum is an element effective in improving the quenching property of a steel sheet. It is expected that containing of this element reduce variation in hardness of the formed products. If this effect of molybdenum is to be utilized, the content of Mo is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Mo only results in saturation of this effect, and thus results in a cost increase. Thus, the content of Mo is preferably 1% or less, more preferably 0.8% or less, and still more preferably 0.5% or less.
- Copper is an element effective in improving the quenching property, and is also useful for improving delayed-fracture resistance and oxidation resistance of a formed product. If this effect of copper is to be utilized, the content of Cu is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Cu may cause a surface flaw during steel sheet manufacturing. This will degrade pickling property, and thus reduce productivity. Thus, the content of Cu is preferably 0.5% or less, and more preferably 0.3% or less.
- Nickel is an element effective in improving the quenching property, and is also useful for improving delayed-fracture resistance and oxidation resistance of a formed product. If this effect of nickel is to be utilized, the content of Ni is preferably greater than 0%, more preferably 0.01% or more, and still more preferably 0.1% or more. However, an excess content of Ni may cause a surface flaw during steel sheet manufacturing. This will degrade pickling property, and thus reduce productivity. Thus, the content of Ni is preferably 0.5% or less, and more preferably 0.3% or less.
- Niobium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness. Thus, if niobium is to be contained, the content of Nb is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more. Meanwhile, an excess content of Nb increases the strength of the steel sheets, thereby reducing the tool life in the blanking step including an operation such as cutting a steel sheet into a predetermined shape before hot press forming. This increases the cost. Thus, the content of Nb is preferably 0.10% or less, and more preferably 0.05% or less.
- Vanadium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness. Thus, if vanadium is to be contained, the content of V is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more. Meanwhile, an excess content of V increases the strength of the steel sheets similarly to the case of Nb, thereby reducing the tool life in the blanking step. This increases the cost. Thus, the content of V is preferably 0.10% or less, and more preferably 0.05% or less.
- Zirconium is an element having an effect of constructing a finer structure, thereby contributing to an increase in toughness. Thus, if zirconium is to be contained, the content of Zr is preferably greater than 0%, more preferably 0.005% or more, and still more preferably 0.010% or more. Meanwhile, an excess content of Zr increases the strength of the steel sheets similarly to the cases of Nb and V, thereby reducing the tool life in the blanking step. This increases the cost. Thus, the content of Zr is preferably 0.10% or less, and more preferably 0.05% or less.
- The method for manufacturing the steel sheets are not limited either. It is sufficient to perform, using general methods, casting, heating, and hot rolling, and pickling followed by cold rolling as needed, and furthermore, annealing as needed. In addition, the hot-rolled steel sheet or cold-rolled steel sheet produced may be plated, as needed, using plating such as zinc-containing plating using a general method, and then further be alloyed as needed.
- Various aspects of technology are disclosed herein as described above, some of which will be summarized below.
- In one aspect of the present invention, the mechanical clinched joint component produced by the method of the present invention is a mechanical clinched joint component formed of two or more steel sheets, where the component includes at least one joint portion having a peel strength of 0.200 kN/mm or greater, and the component has a hardness of 360 Hv or greater.
- According to the present invention, the method for manufacturing the mechanical clinched joint component sequentially includes heating the two or more steel sheets to an Ac3 temperature or above; and performing mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) below and of equation (2) below:
- The two or more steel sheets used in the method for manufacturing the mechanical clinched joint component may each have a constituent composition in mass% satisfying:
- C: 0.15 to 0.4%,
- Si: more than 0% to 2% or less, and
- at least one of Mn and Cr: 1.0 to 5.0% in total, and
- further satisfying Ti: 0% or more to 0.10% or less, B: 0% or more to 0.005% or less, Al: 0% or more to 0.5% or less, Mo: 0% or more to 1% or less, Cu: 0% or more to 0.5% or less, Ni: 0% or more to 0.5% or less, Nb: 0% or more to 0.10% or less, V: 0% or more to 0.10% or less, and Zr: 0% or more to 0.10% or less,
- and the balance being iron and incidental impurities.
- The method for manufacturing the mechanical clinched joint component may perform the step of performing mechanical clinch joining a plurality of times.
- The present invention will be described below more specifically using examples. However, the present invention is not limited to examples described below.
- A steel sheet A and a steel sheet B having constituent compositions illustrated in Table 3 were each used to prepare two specimens having a dimension of 150 mm × 50 mm × sheet thickness 1.4 mm, and each pair of the two test specimens was mechanically clinched together using the tool illustrated in
FIG. 3 . In more detail, referring toFIG. 3 , thesteel sheet 1 and theother steel sheet 2 heated at 930°C for 4 minutes were stacked together, crosswise, one on top of another, and were placed on thesupport platform 3 between the joiningpunch 6 included in the joiningpunch holder 7 and the joiningdie 4 included in the joiningdie holder 5. After air cooling to the joining start temperature described below, the joiningdie 4 was lowered to perform mechanical clinch joining under the conditions listed below, and test specimens representing the component were thus produced. - Holder pressure: 3 ton-force (tonf)
Punch diameter: Dp = 10.0 mm
Die diameter: D = 14.0 mm
Forming rate: 20 spm
Joining start temperature: as illustrated in Table 4 for the steel sheet A, and as illustrated in Table 5 for the steel sheet B
Bottom-dead-center holding time: as illustrated in Table 4 for the steel sheet A, and as illustrated in Table 5 for the steel sheet B - The hardness and peel strength of the test specimens produced were determined as follows.
- As the hardness of a test specimen, Vickers hardness Hv was determined at three points per steel sheet under a load condition of 1 kgf in a portion other than the joint portion, i.e., in a holder portion of the component, at a location of 1/4 sheet thickness of each steel sheet that constitute the component. The results of the three points were averaged for each steel sheet, and the lowest average value in the steel sheets was used as the hardness of that component. Evaluation was made against the following criteria.
- Very Good: Hv ≥ 450
Good: 450 > Hv ≥ 360
Poor: 360 > Hv - The cross tensile strength CTS (kN) of each test specimen was measured according to JIS Z 3137. This CTS value was divided by the circumference L (mm) of the joint portion to calculate the cross tensile strength per unit peripheral length CTS/L (kN/mm) of the joint portion as the peel strength. A peel strength corresponding to this CTS/L value of 0.200 kN/mm or greater was classified as high.
-
FIGs. 4A and 4B are diagrams illustrating cross sections of the die used and of the joint component produced. As illustrated inFIG. 4B , the joint diameter d of the joint component was measured, and then a value of d/D was also calculated by dividing this joint diameter d by the die diameter D illustrated inFIG. 4A . A smaller d/D value indicates stronger joining, and the value of d/D is preferably 1.029 or less. -
[Table 3] STEEL SHEET CONSTITUENT COMPOSITION (MASS%) WITH BALANCE OF IRON AND INCIDENTAL IMPURITIES OTHER THAN P, S, AND N Ceq (MASS%) Ac3 (°C) C Si Mn P S Cr Ti B Al N A 0.231 0.18 1.29 0.012 0.0030 0.21 0.024 0.0029 0.039 0.0049 0.496 910 B 0.219 1.13 2.21 0.011 0.0010 0.02 0.023 0.0019 0.045 0.0036 0.638 928 [Table 4] No. STEEL SHEET Ceq (MASS%) JOINING START TEMPERATURE T (°C) BOTTOM-DEAD-CENTER HOLDING TIME t (SECOND) Ceq×f(T.t) -0.00071 × T+0.993 HARDNESS Hv PEEL STRENGTH CTS/L (kN/mm) d/D 1 A 0.496 800 2.5 0.2742 0.4250 GOOD 0.280 1.023 2 800 5 0.2768 0.4250 GOOD 0.302 1.017 3 800 7.5 0.2794 0.4250 GOOD 0.307 1.015 4 800 10 0.2820 0.4250 VERY GOOD 0.307 1.024 5 700 2.5 0.2380 0.4960 GOOD 0.254 1.029 6 700 5 0.2406 0.4960 GOOD 0.263 1.028 7 700 7.5 0.2432 0.4960 GOOD 0.248 1.027 8 700 10 0.2458 0.4960 VERY GOOD 0.269 1.024 9 600 10 0.2096 0.5670 POOR 0.104 1.030 Ceq × f(T,t) =Ceq × (0.00209 × t+0.000731 × T-0.0365) [Table 5] No. STEEL SHEET Ceq (MASS%) JOINING START TEMPERATURE T (°C) BOTTOM-DEAD-CENTER HOLDING TIME t (SECOND) Ceq × f(T,t) -0.00071 × T+0.993 HARDNESS Hv PEEL STRENGTH CTS/L (kN/mm) d/ D 1 800 0 0.3500 0.4250 VERY GOOD 0.316 1.0270 2 800 2.5 0.3533 0.4250 VERY GOOD 0.337 1.0130 3 800 5 0.3567 0.4250 VERY GOOD 0.349 1.0111 4 800 7.5 0.3600 0.4250 VERY GOOD 0.369 1.0093 5 800 10 0.3633 0.4250 VERY GOOD 0.381 0.9963 6 700 0 0.3033 0.4960 VERY GOOD 0.319 1.0125 7 700 2.5 0.3067 0.4960 VERY GOOD 0.343 1.0195 8 B 0.638 700 10 0.3167 0.4960 VERY GOOD 0.342 1.0111 9 600 0 0.2567 0.5670 VERY GOOD 0.248 1.0158 10 600 10 0.2700 0.5670 VERY GOOD 0.313 1.0181 11 500 0 0.2100 0.6380 VERY GOOD 0.212 1.0176 12 500 10 0.2233 0.6380 VERY GOOD 0.282 1.0204 13 400 0 0.1633 0.7090 NOT JOINABLE 14 400 2.5 0.1667 0.7090 VERY GOOD 0.137 1.0310 15 400 5 0.1700 0.7090 VERY GOOD 0.150 1.0300 16 300 0 0.1167 0.7800 CRACK OCCURRED DURING JOINING Ceq × f(T,t) =Ceq × (0.00209 × t+0.000731 × T-0.0365) - First, Table 4 shows the following results for the case of the steel sheet A. Specimens Nos. 1 to 8 are those of examples of performing mechanical clinch joining so that the carbon equivalent Ceq of the steel sheets used, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining satisfy relationships of predetermined equation (1) and equation (2). In these examples, joining was performed successfully without occurrence of a crack, and the component produced had a high hardness Hv corresponding to 1180 MPa or greater, and a peel strength CTS/L of 0.200 kN/mm or greater. Among these, as shown by the results of Nos. 4 and 8, a bottom-dead-center holding time of 10 seconds resulted in satisfactory hardness. In particular, as shown by the result of No. 4, a combination of a joining start temperature of 800°C and a bottom-dead-center holding time of 10 seconds further resulted in sufficiently high peel strength.
- On the contrary, specimen No. 9 had a joining start temperature that did not satisfy equation (2), thereby caused a soft phase to segregate. Therefore, even though no cracks occurred, the hardness was low, and the peel strength was also low.
- Next, Table 5 shows the following results for the case of the steel sheet B. Specimens Nos. 1 to 12 are those of examples of performing mechanical clinch joining so that the carbon equivalent Ceq of the steel sheets used, and the bottom-dead-center holding time t and the joining start temperature T during mechanical clinch joining satisfy relationships of predetermined equation (1) and equation (2). In these examples, joining was performed successfully without occurrence of a crack, and the component produced had a high hardness Hv corresponding to 1180 MPa or greater, and a peel strength CTS/L of 0.200 kN/mm or greater. In particular, a joining start temperature of 500°C or higher achieved both Hv ≥ 450 and CTS/L ≥ 0.200kN/mm even without holding at the bottom dead center.
- Among these, as shown by the result of No. 5, a combination of a joining start temperature of 800°C and a bottom-dead-center holding time of 10 seconds resulted in sufficiently high peel strength. Observation of a cross section of this specimen No. 5 as illustrated in
FIG. 5A shows that planar pressure exerted at the interface between the heated steel sheets during mechanical clinch joining accelerates interdiffusion to cause diffusion joining, as illustrated inFIG. 5B , and inFIG. 5C that illustrates an enlarged image of the ellipse portion ofFIG. 5B . It is likely that this diffusion joining has provided higher peel strength in specimen No. 5. - As illustrated in Table 5, in the case of the steel sheet B, steel sheets can be joined together using a joining start temperature from 500 to 600°C, and in addition, the bottom-dead-center holding time can be reduced or omitted. This enables joining in a multiple-step process, and joining to a vertical wall portion such as one illustrated in
FIGs. 2A to 2C is also possible. - In contrast, a joining start temperature of 400°C caused no cracks to occur, but as shown by the result of No. 13 in particular, omission of holding at the bottom dead center caused failure in staking the portions to be joined. Thus, the steel sheets were not joinable. In addition, as shown by the results of Nos. 14 and 15, the holding times of 2.5 seconds and of 5 seconds could provide the hardness satisfying Hv ≥ 360, but the peel strengths were unsatisfactory.
- In addition, as shown by the result of No. 16, a joining start temperature of 300°C caused a crack to occur during joining.
-
FIG. 6 drawn based on the results of Table 4 and Table 5 above shows that the left-side values of equation (1) and CTS/L values almost match. - In this Example, evaluation was made on properties for cases in which specimens of the steel sheet B were joined together at a same portion multiple times. In more detail, the procedures for the respective examples of Table 6 were as follows.
- No. 1: heated to 930°C → air-cooled to a joining start temperature of 800°C → mechanical clinch joining → property evaluation
- No. 2: heated to 930°C → air-cooled to a joining start temperature of 800°C → first mechanical clinch joining → second mechanical clinch joining → property evaluation
- No. 3: heated to 930°C → air-cooled to a joining start temperature of 800°C → first mechanical clinch joining → second mechanical clinch joining → third mechanical clinch joining → property evaluation
- The mechanical clinch joining described above was performed using the tool illustrated in
FIG. 3 under the conditions illustrated in Table 6. The properties, i.e., hardness, peel strength, and d/D, of the test specimens produced were determined similarly to Example 1. The results are illustrated in Table 6.[Table 6] No. STEEL SHEET Ceq (MASS%) JOINING START TEMPERATURE T (°C) BOTTOM-DEAD-CENTER HOLDING TIME t (SECOND) NUMBER OF JOINING OPERATIONS Ceq × f(T,t) -0.00071 × T+0.993 HARDNESS Hv PEEL STRENGTH CTS/L (kN/mm) d/D 1 B 0.638 800 0 1 0.3500 0.4250 VERY GOOD 0.316 1.027 2 800 0 2 0.3533 0.4250 VERY GOOD 0.324 1.025 3 800 0 3 0.3567 0.4250 VERY GOOD 0.334 1.021 Ceq × f(T,t)=Ceq × (0.00209 × t+0.000731 × T-0.0365) - Table 6 shows that performing a higher number of the joining operations increases the peel strength CTS/L. This may be because, despite the bottom-dead-center holding time being zero, pressing a same portion consecutively increases the number of contacts between the steel sheet and the tool to increase the total contact time therebetween, thereby decreasing the d/D value.
- The present application is based on Japanese Patent Application No.
2016-072486 filed on March 31, 2016 - To describe the invention, the invention has been described in the foregoing description appropriately and sufficiently using embodiments with reference to specific examples and the like. However, it is to be understood that changes and/or modifications to the foregoing embodiments will readily occur to those skilled in the art. Therefore, unless a change or modification made by those skilled in the art is beyond the scope of the appended claims, such change or modification is to be embraced within the scope of the appended claims.
- The present invention has a wide range of industrial applicability in technical fields relating to mechanical clinch joining.
Claims (3)
- A method for manufacturing a mechanical clinched joint component, the method sequentially comprising:heating two or more steel sheets to an Ac3 temperature or above, the steel sheets having a tensile strength of 1180 MPa or more; andperforming mechanical clinch joining so that a carbon equivalent Ceq of the steel sheets, and a bottom-dead-center holding time t and a joining start temperature T during mechanical clinch joining satisfy relationships of equation (1) below and of equation (2) below:whereinthe mechanical clinched joint component includes at least one joint portion,Ac3 transformation point (°C) = 910 - 203 × [C]0.5 - 15.2 × [Ni] + 44.7 × [Si] + 104 × [V] + 31.5 × [Mo] + 13.1 × [W] - 30 × [Mn] - 11 × [Cr] - 20 × [Cu] + 700 × [P] + 400 × [Al] + 400 [Ti], andhot press forming is also performed in the step of performing mechanical clinch joining.
- The method for manufacturing the mechanical clinched joint component according to claim 1, wherein the two or more steel sheets each has a constituent composition in mass% satisfying:C: 0.15 to 0.4%,Si: more than 0% to 2% or less, andat least one of Mn and Cr: 1.0 to 5.0% in total, andfurther satisfying Ti: 0% or more to 0.10% or less, B: 0% or more to 0.005% or less, Al: 0% or more to 0.5% or less, Mo: 0% or more to 1% or less, Cu: 0% or more to 0.5% or less, Ni: 0% or more to 0.5% or less, Nb: 0% or more to 0.10% or less, V: 0% or more to 0.10% or less, and Zr: 0% or more to 0.10% or less,and the balance being iron and incidental impurities.
- The method for manufacturing the mechanical clinched joint component according to claim 1, wherein the step of performing mechanical clinch joining is performed a plurality of times.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2016072486A JP6692200B2 (en) | 2016-03-31 | 2016-03-31 | Method for manufacturing mechanical clinch joint parts |
PCT/JP2017/009224 WO2017169588A1 (en) | 2016-03-31 | 2017-03-08 | Mechanical clinch joining component and method for manufacturing same |
Publications (3)
Publication Number | Publication Date |
---|---|
EP3437753A1 EP3437753A1 (en) | 2019-02-06 |
EP3437753A4 EP3437753A4 (en) | 2019-10-09 |
EP3437753B1 true EP3437753B1 (en) | 2020-12-09 |
Family
ID=59964082
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP17774133.7A Active EP3437753B1 (en) | 2016-03-31 | 2017-03-08 | Method for manufacturing a mechanical clinch joining component |
Country Status (11)
Country | Link |
---|---|
US (1) | US20190105700A1 (en) |
EP (1) | EP3437753B1 (en) |
JP (1) | JP6692200B2 (en) |
KR (1) | KR102133176B1 (en) |
CN (1) | CN108883458B (en) |
BR (1) | BR112018070180B1 (en) |
CA (1) | CA3018539C (en) |
ES (1) | ES2846348T3 (en) |
MX (1) | MX2018011735A (en) |
RU (1) | RU2699427C1 (en) |
WO (1) | WO2017169588A1 (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6891763B2 (en) * | 2017-11-08 | 2021-06-18 | トヨタ自動車株式会社 | Vehicle joint structure |
KR102043529B1 (en) * | 2017-12-28 | 2019-11-11 | 현대제철 주식회사 | Method for controlling coil width and apparatus thereof |
MX2022010141A (en) * | 2020-02-26 | 2022-12-06 | Nippon Steel Corp | Method for manufacturing layered hot stamping molded body and layered hot stamping molded body. |
JP7348581B2 (en) * | 2020-08-31 | 2023-09-21 | 日本製鉄株式会社 | Manufacturing method of molded parts, molded parts, and automobile parts |
DE102020128367A1 (en) * | 2020-10-28 | 2022-04-28 | Te Connectivity Germany Gmbh | Arrangement with a sheet metal stack assembled from at least three sheet metal layers lying one on top of the other |
CA3217083A1 (en) * | 2021-04-28 | 2022-11-03 | Yuchao LIU | Self-piercing riveting with barrier layer |
US20230042057A1 (en) * | 2021-08-09 | 2023-02-09 | Kuka Systems North America Llc | Apparatus and methods for forming an attachment pad in high strength steel materials |
Family Cites Families (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19714129A1 (en) * | 1997-04-05 | 1998-10-15 | Eckold Vorrichtung | Joining method and device |
JP4334738B2 (en) * | 2000-05-16 | 2009-09-30 | 日本鋳造株式会社 | High strength high toughness cast steel |
KR100468258B1 (en) * | 2002-08-21 | 2005-01-27 | 주식회사 성우하이텍 | Metallic patterns of a simultaneous forming press with clinching of multi-panel |
WO2004048013A1 (en) * | 2002-11-26 | 2004-06-10 | Volvo Aero Corporation | Method of typing two or more components together |
JP2005131699A (en) * | 2003-10-31 | 2005-05-26 | Nisshin Steel Co Ltd | Calking method for stainless steel sheet |
JP2006035244A (en) * | 2004-07-23 | 2006-02-09 | Auto Network Gijutsu Kenkyusho:Kk | Cold friction welding method, and metal welded body |
JP2006321405A (en) | 2005-05-20 | 2006-11-30 | Aisin Takaoka Ltd | Door impact beam and its manufacturing method |
KR101531815B1 (en) * | 2011-01-14 | 2015-06-25 | 가부시키가이샤 고베 세이코쇼 | Press forming method for steel plate |
US9259774B2 (en) * | 2011-05-03 | 2016-02-16 | GM Global Technology Operations LLC | Clinching method and tool for performing the same |
EP2733051A4 (en) | 2011-07-12 | 2015-02-25 | Honda Motor Co Ltd | Side outer panel for vehicle |
JP2013022628A (en) * | 2011-07-22 | 2013-02-04 | Aster:Kk | Method of manufacturing metal junction body and metal junction body |
JP5704721B2 (en) * | 2011-08-10 | 2015-04-22 | 株式会社神戸製鋼所 | High strength steel plate with excellent seam weldability |
JP5813414B2 (en) * | 2011-08-22 | 2015-11-17 | ツツミ産業株式会社 | Caulking method of Mg alloy plate |
ES2648415T5 (en) * | 2012-03-30 | 2021-02-15 | Voestalpine Stahl Gmbh | Cold Rolled High Strength Steel Sheet And Manufacturing Process Of Such Sheet Steel |
TWI463018B (en) * | 2012-04-06 | 2014-12-01 | Nippon Steel & Sumitomo Metal Corp | High strength steel plate with excellent crack arrest property |
JP5978040B2 (en) * | 2012-07-24 | 2016-08-24 | 中部冷間株式会社 | Sheet metal bonding method |
US8636197B1 (en) * | 2012-10-04 | 2014-01-28 | Ford Global Technologies, Llc | Bonding of roof panels |
RU155276U1 (en) * | 2015-04-06 | 2015-09-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Казанский национальный исследовательский технический университет им. А.Н. Туполева-КАИ" (КНИТУ-КАИ) | DEVICE FOR CONNECTING PARTS FROM SHEET METAL |
-
2016
- 2016-03-31 JP JP2016072486A patent/JP6692200B2/en active Active
-
2017
- 2017-03-08 WO PCT/JP2017/009224 patent/WO2017169588A1/en active Application Filing
- 2017-03-08 BR BR112018070180-7A patent/BR112018070180B1/en active IP Right Grant
- 2017-03-08 EP EP17774133.7A patent/EP3437753B1/en active Active
- 2017-03-08 CN CN201780020625.6A patent/CN108883458B/en active Active
- 2017-03-08 RU RU2018138172A patent/RU2699427C1/en active
- 2017-03-08 CA CA3018539A patent/CA3018539C/en active Active
- 2017-03-08 US US16/089,494 patent/US20190105700A1/en not_active Abandoned
- 2017-03-08 ES ES17774133T patent/ES2846348T3/en active Active
- 2017-03-08 MX MX2018011735A patent/MX2018011735A/en unknown
- 2017-03-08 KR KR1020187031392A patent/KR102133176B1/en active IP Right Grant
Non-Patent Citations (1)
Title |
---|
None * |
Also Published As
Publication number | Publication date |
---|---|
US20190105700A1 (en) | 2019-04-11 |
BR112018070180B1 (en) | 2022-11-29 |
JP6692200B2 (en) | 2020-05-13 |
WO2017169588A1 (en) | 2017-10-05 |
ES2846348T3 (en) | 2021-07-28 |
EP3437753A4 (en) | 2019-10-09 |
EP3437753A1 (en) | 2019-02-06 |
KR102133176B1 (en) | 2020-07-13 |
CA3018539C (en) | 2020-12-29 |
CA3018539A1 (en) | 2017-10-05 |
CN108883458A (en) | 2018-11-23 |
MX2018011735A (en) | 2018-12-19 |
CN108883458B (en) | 2020-07-31 |
RU2699427C1 (en) | 2019-09-05 |
JP2017177206A (en) | 2017-10-05 |
KR20180132758A (en) | 2018-12-12 |
BR112018070180A2 (en) | 2019-01-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP3437753B1 (en) | Method for manufacturing a mechanical clinch joining component | |
KR102296362B1 (en) | Hot-pressed member and manufacturing method thereof, cold-rolled steel sheet for hot pressing, and manufacturing method thereof | |
EP2266722B1 (en) | Method of production of a high strength part | |
EP2824196B1 (en) | Method for manufacturing press-formed product and press-formed product | |
JP5639678B2 (en) | Manufacturing method of hot press-formed steel member and hot press-formed steel member | |
JP6447752B2 (en) | Automotive parts having resistance welds | |
JP5803836B2 (en) | Hot pressed steel plate member, its manufacturing method and hot pressed steel plate | |
EP2578718A1 (en) | High-strength molten-zinc-plated steel sheet having excellent bendability and weldability, and process for production thereof | |
CN112930413A (en) | High-strength steel sheet and method for producing same | |
KR20140117584A (en) | Steel sheet, plated steel sheet, method for producing steel sheet, and method for producing plated steel sheet | |
JP6606897B2 (en) | Steel plate for heat treatment, method for producing the same, and hot stamped product | |
CN113490758B (en) | Hot-pressed member, cold-rolled steel sheet for hot pressing, and method for producing same | |
EP3202519B1 (en) | Hot stamped part having a brazed joint and manufacturing method for the hot stamped part | |
US20190366686A1 (en) | Alloyed al plated steel sheet for hot stamping and hot stamped steel member | |
WO2020158285A1 (en) | Hot-pressed member, cold-rolled steel sheet for hot-pressed member, and methods respectively for producing these products | |
JP2003089848A5 (en) | ||
JP2004332100A (en) | High-strength thin steel sheet superior in hydrogen embrittlement resistance, weldability, and hole-expandability and manufacturing method therefor | |
EP3301197A1 (en) | Method for cold deformation of an austenitic steel | |
US20210301364A1 (en) | Producing a hardened steel product | |
EP4273281A1 (en) | Hot-stamped molded body | |
WO2003069010A1 (en) | Steel sheet for container excellent in formability and properties at weld, and method for producing the same | |
JP7315129B1 (en) | Hot press parts and steel sheets for hot press | |
JP3662335B2 (en) | Welded steel sheet for composite forming | |
WO2020170530A1 (en) | Hot-pressed member and method for manufacturing same, and method for manufacturing steel sheet for hot-pressed members | |
WO2023188792A1 (en) | Hot press member and steel plate for hot pressing |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20181016 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
A4 | Supplementary search report drawn up and despatched |
Effective date: 20190909 |
|
RIC1 | Information provided on ipc code assigned before grant |
Ipc: C22C 38/38 20060101ALI20190903BHEP Ipc: C22C 38/00 20060101ALI20190903BHEP Ipc: C22C 38/06 20060101ALI20190903BHEP Ipc: B21D 22/20 20060101ALI20190903BHEP Ipc: C22C 38/04 20060101ALI20190903BHEP Ipc: C22C 38/28 20060101ALI20190903BHEP Ipc: C22C 38/02 20060101ALI20190903BHEP Ipc: C22C 38/32 20060101ALI20190903BHEP Ipc: B21D 39/03 20060101AFI20190903BHEP |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20200721 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1342885 Country of ref document: AT Kind code of ref document: T Effective date: 20201215 Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602017029322 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: TRGR |
|
REG | Reference to a national code |
Ref country code: SK Ref legal event code: T3 Ref document number: E 36372 Country of ref document: SK |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210310 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210309 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210309 Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20201209 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2846348 Country of ref document: ES Kind code of ref document: T3 Effective date: 20210728 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210409 Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 602017029322 Country of ref document: DE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210409 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
26N | No opposition filed |
Effective date: 20210910 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20210331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210308 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210308 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210409 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210331 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: UEP Ref document number: 1342885 Country of ref document: AT Kind code of ref document: T Effective date: 20201209 |
|
P01 | Opt-out of the competence of the unified patent court (upc) registered |
Effective date: 20230523 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20170308 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 20230407 Year of fee payment: 7 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20231229 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 20240226 Year of fee payment: 8 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201209 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20231229 Year of fee payment: 8 Ref country code: CZ Payment date: 20240216 Year of fee payment: 8 Ref country code: GB Payment date: 20240108 Year of fee payment: 8 Ref country code: SK Payment date: 20240123 Year of fee payment: 8 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: TR Payment date: 20240219 Year of fee payment: 8 Ref country code: SE Payment date: 20240103 Year of fee payment: 8 |