EP0410033A1 - Verfahren zur Herstellung von Werkstücken aus ferritischem Stahl - Google Patents
Verfahren zur Herstellung von Werkstücken aus ferritischem Stahl Download PDFInfo
- Publication number
- EP0410033A1 EP0410033A1 EP89113767A EP89113767A EP0410033A1 EP 0410033 A1 EP0410033 A1 EP 0410033A1 EP 89113767 A EP89113767 A EP 89113767A EP 89113767 A EP89113767 A EP 89113767A EP 0410033 A1 EP0410033 A1 EP 0410033A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- nickel
- workpiece
- chromium
- steel
- coating
- 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.)
- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims abstract description 23
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 18
- 239000010959 steel Substances 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 9
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 46
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 23
- 238000000576 coating method Methods 0.000 claims abstract description 19
- 239000011248 coating agent Substances 0.000 claims abstract description 16
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 9
- 239000011651 chromium Substances 0.000 claims abstract description 9
- 239000010941 cobalt Substances 0.000 claims abstract description 9
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 9
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 9
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 6
- 239000001301 oxygen Substances 0.000 claims abstract description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims abstract description 6
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 5
- 239000000956 alloy Substances 0.000 claims abstract description 5
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 5
- 230000007717 exclusion Effects 0.000 claims abstract description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 11
- 229910052750 molybdenum Inorganic materials 0.000 claims description 11
- 239000011733 molybdenum Substances 0.000 claims description 11
- 238000005553 drilling Methods 0.000 claims description 6
- 238000009792 diffusion process Methods 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 238000005260 corrosion Methods 0.000 description 13
- 230000007797 corrosion Effects 0.000 description 13
- 229910052739 hydrogen Inorganic materials 0.000 description 13
- 239000001257 hydrogen Substances 0.000 description 13
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 12
- 239000010410 layer Substances 0.000 description 12
- 238000010438 heat treatment Methods 0.000 description 7
- 229910000669 Chrome steel Inorganic materials 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000011162 core material Substances 0.000 description 3
- 238000009713 electroplating Methods 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- BIJOYKCOMBZXAE-UHFFFAOYSA-N chromium iron nickel Chemical compound [Cr].[Fe].[Ni] BIJOYKCOMBZXAE-UHFFFAOYSA-N 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000005246 galvanizing Methods 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- BXNRPWOFOQNQDE-UHFFFAOYSA-N boric acid;nickel Chemical compound [Ni].OB(O)O BXNRPWOFOQNQDE-UHFFFAOYSA-N 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 238000010349 cathodic reaction Methods 0.000 description 1
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 1
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- UGKDIUIOSMUOAW-UHFFFAOYSA-N iron nickel Chemical compound [Fe].[Ni] UGKDIUIOSMUOAW-UHFFFAOYSA-N 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 1
- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 1
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/001—Heat treatment of ferrous alloys containing Ni
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0093—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for screws; for bolts
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/48—After-treatment of electroplated surfaces
- C25D5/50—After-treatment of electroplated surfaces by heat-treatment
Definitions
- the invention relates to a method for producing workpieces from ferritic steel according to the preamble of patent claim 1.
- the workpieces should have a high level of hardness and wear resistance. They should also be corrosion-resistant. Carbon steels are not suitable for these applications because they are particularly sensitive to corrosive media. It is therefore known to use rust-resistant alloy steels containing, for example, chromium, nickel, cobalt, molybdenum and the like. Such Alloyed steels are usually relatively inert and can be adjusted to the desired hardness because of their hardenability. Nevertheless, chromium steel is not permitted for the production of fasteners in the construction sector, for example for the production of screws, especially self-drilling screws. The reason is the hydrogen-induced cracking (hydrogen embrittlement).
- the hydrogen contained in the lanyard can lead to said crack formation.
- the hydrogen that is applied to the connecting means from the outside for example, in the event of a cathodic reaction in the event of corrosion - such a process affects the fatigue strength of a screw, for example, which affects the safety of a building structure.
- coatings such as galvanizing, which represents a barrier for the hydrogen.
- the protective layer will be damaged during use or that the formation of cracks will not be completely excluded by nature, so that hydrogen embrittlement cannot be stopped in this way.
- the invention has for its object to provide a process for the production of workpieces made of ferritic steel, in which the workpieces with high hardness and strength have a high corrosion resistance that comes close to that of austenitic chromium-nickel steels and in which hydrogen-induced crack formation is avoided .
- the workpiece is formed from non-convertible chrome steel with a chrome content of at least 13%.
- workpieces made of chrome steel are known per se.
- the workpiece is provided with a coating of nickel or an alloy essentially containing nickel or cobalt with a thickness of at least 5 m.
- the workpiece is then brought to the desired hardness in the absence of oxygen at at least 850 ° C. by heat treatment, the diffusion layer with the special properties being formed simultaneously from the coating and the base material.
- the treated workpieces have a nickel jacket with an underlying chromium-nickel-iron layer of varying composition.
- the existing hydrogen is expelled during the heat treatment.
- Hydrogen which can arise during a corrosion process, for example, cannot penetrate the nickel-iron diffusion layer.
- the core of the workpiece also consists of a high-quality, non-convertible steel and that the diffusion of nickel into the chromium steel or vice versa of chromium in the nickel plating results in a relatively thick austenitic intermediate layer which provides an effective barrier against the penetration of Represents hydrogen.
- no hardness-producing substances have to diffuse through the nickel layer in order to achieve the usability of the workpiece.
- the hardening and the generation of the corrosion resistance as a result of austenitic coatings containing chromium and possibly molybdenum on an inherently inert material takes place in a single step. If the chromium steel contains molybdenum in one embodiment of the invention, the molybdenum content of the austenitic intermediate layer has a favorable effect on the repassivation.
- a coating of chromium, cobalt, molybdenum or copper with a thickness of at least two m is applied to the nickel coating or the coating made of nickel or an alloy containing cobalt.
- an austenitic chromium-nickel iron layer is formed on the chrome steel, which seamlessly merges with the martensitic chrome steel.
- the method according to the invention leads to workpieces which can be adjusted to the desired hardness with approximately the same good corrosion resistance.
- the workpiece is formed from steel containing nickel or molybdenum, the workpiece is then provided with a chrome coating with a thickness of min at least 5 m and then in the absence of oxygen at least 850 ° C by heat treatment to the desired hardness. In this process, a corrosion protection coating similar to that described above is obtained.
- additional corrosion protection by galvanizing or cadmium coating can be dispensed with.
- additional layers can be applied to improve the sliding behavior (reduction of friction when using the connecting means).
- metallic coatings are also conceivable.
- the method according to the invention can be used for various high-quality workpieces, for example for knife blades, surgical instruments or other highly wear-resistant tools and components. It is particularly advantageous for the production of fasteners, such as screws or the like, in particular self-drilling screws, in construction, for which a high level of corrosion resistance and great hardness is required for safety reasons.
- the hardness is required, for example, for self-drilling screws so that they are able to drill a core hole even in relatively hard carrier material.
- Chrome steel Material according to DIN 17006: 1.1% carbon; 15% chromium; 0.5 molybdenum Material No. 4112 according to DIN 17006: 0.9% carbon; 18% chromium; 1.2 molybdenum
- a self-drilling screw for example made of the above chrome steel, is electroplated with a nickel coating of 10 m thick or a coating of 5 m thick nickel and about 2 m thick chrome.
- Electroplating conditions for the nickel layer Temperature: 50 to 70 ° C pH: 6 to 3 Current density: 2 to 9 A / d cm2 Nickel bath: Nickel sulfate: 300 g / l Nickel chloride: 40 g / l Nickel boric acid: 40 g / l
- Electroplating conditions for the chrome layer Temperature: 55 ° C Current density: 40 A / d cm2 Chrome bath: Chromic acid: CrO3 350 g / l Sulfuric acid: density 1.84 2.5 g / l
- electroplating can also be carried out using the currentless method.
- the heat treatment takes place in the oven with the exclusion of oxygen at a temperature of, for example, 1000 ° C over a period of 10 minutes.
- the temperature depends on the core material used and the time on the hardness to be set.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Electroplating Methods And Accessories (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19883804824 DE3804824A1 (de) | 1988-02-17 | 1988-02-17 | Verfahren zur herstellung von werkstuecken aus ferritischem stahl |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0410033A1 true EP0410033A1 (de) | 1991-01-30 |
Family
ID=6347532
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP89113767A Withdrawn EP0410033A1 (de) | 1988-02-17 | 1989-07-26 | Verfahren zur Herstellung von Werkstücken aus ferritischem Stahl |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0410033A1 (en, 2012) |
| AU (1) | AU3931889A (en, 2012) |
| DE (1) | DE3804824A1 (en, 2012) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3804824A1 (de) * | 1988-02-17 | 1989-09-07 | Itw Ateco Gmbh | Verfahren zur herstellung von werkstuecken aus ferritischem stahl |
| US6443211B1 (en) * | 1999-08-31 | 2002-09-03 | Cummins Inc. | Mettallurgical bonding of inserts having multi-layered coatings within metal castings |
| DE102007000485B3 (de) | 2007-09-05 | 2008-10-16 | Hilti Aktiengesellschaft | Befestigungselement |
| DE102021118765A1 (de) | 2021-07-20 | 2023-01-26 | Kamax Holding Gmbh & Co. Kg | Bauteil mit integrierter Nickeldiffusionsschicht |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1608694A (en) * | 1925-08-10 | 1926-11-30 | John R Cain | Corrosion-resistant article and method of making the same |
| GB456005A (en) * | 1935-05-23 | 1936-11-02 | Arnold James Claisse | Safety razor blades and the like and the production thereof |
| FR1350057A (fr) * | 1962-12-11 | 1964-01-24 | Acieries Du Temple | Acier à coupe rapide ou tenace à chaud |
| US3344817A (en) * | 1965-05-28 | 1967-10-03 | Illinois Tool Works | Method of selectively hardening a corrosion resistant part and the article produced thereby |
| DE3804824A1 (de) * | 1988-02-17 | 1989-09-07 | Itw Ateco Gmbh | Verfahren zur herstellung von werkstuecken aus ferritischem stahl |
-
1988
- 1988-02-17 DE DE19883804824 patent/DE3804824A1/de active Granted
-
1989
- 1989-07-26 EP EP89113767A patent/EP0410033A1/de not_active Withdrawn
- 1989-08-04 AU AU39318/89A patent/AU3931889A/en not_active Abandoned
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1608694A (en) * | 1925-08-10 | 1926-11-30 | John R Cain | Corrosion-resistant article and method of making the same |
| GB456005A (en) * | 1935-05-23 | 1936-11-02 | Arnold James Claisse | Safety razor blades and the like and the production thereof |
| FR1350057A (fr) * | 1962-12-11 | 1964-01-24 | Acieries Du Temple | Acier à coupe rapide ou tenace à chaud |
| US3344817A (en) * | 1965-05-28 | 1967-10-03 | Illinois Tool Works | Method of selectively hardening a corrosion resistant part and the article produced thereby |
| DE3804824A1 (de) * | 1988-02-17 | 1989-09-07 | Itw Ateco Gmbh | Verfahren zur herstellung von werkstuecken aus ferritischem stahl |
Non-Patent Citations (3)
| Title |
|---|
| CHEMICAL ABSTRACTS, Band 102, Nr. 2, Januar 1985, Kurzfassung Nr. 102:14116d, "Corrosion-resistant stainless steel sheet", Columbus, Ohio, US; & JP-A-59 140 389 (NIPPON STEEL) 11-08-1984 * |
| PATENT ABSTRACTS OF JAPAN, Band 12, Nr. 223, 24. Juni 1988; & JP-A-63 20 435 (TOOPURA) 28-01-1988 * |
| PATENT ABSTRACTS OF JAPAN, Band 12, Nr. 5, 8. Januar 1988; & JP-A-62 161 950 (NIIGATA ENG. CO.) 17-07-1987 * |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3804824C2 (en, 2012) | 1989-11-30 |
| DE3804824A1 (de) | 1989-09-07 |
| AU3931889A (en) | 1991-02-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 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 |
|
| 17P | Request for examination filed |
Effective date: 19900516 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE CH DE ES FR GB IT LI LU NL SE |
|
| 17Q | First examination report despatched |
Effective date: 19920909 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
| 18D | Application deemed to be withdrawn |
Effective date: 19931228 |