CN116944645A - Spot welding process for phosphorus-added high-strength galvanized aluminum-magnesium steel plate - Google Patents
Spot welding process for phosphorus-added high-strength galvanized aluminum-magnesium steel plate Download PDFInfo
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- CN116944645A CN116944645A CN202310972988.7A CN202310972988A CN116944645A CN 116944645 A CN116944645 A CN 116944645A CN 202310972988 A CN202310972988 A CN 202310972988A CN 116944645 A CN116944645 A CN 116944645A
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- spot welding
- phosphorus
- steel plate
- welding
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- 238000003466 welding Methods 0.000 title claims abstract description 109
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 58
- 239000010959 steel Substances 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 title claims abstract description 42
- 230000008569 process Effects 0.000 title claims abstract description 31
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 title claims abstract description 21
- 238000003825 pressing Methods 0.000 claims abstract description 9
- 238000010008 shearing Methods 0.000 claims abstract description 8
- 238000001816 cooling Methods 0.000 claims abstract description 7
- 238000007747 plating Methods 0.000 claims description 12
- 239000000126 substance Substances 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 4
- 229910052725 zinc Inorganic materials 0.000 claims description 4
- 239000007772 electrode material Substances 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 5
- 238000004519 manufacturing process Methods 0.000 description 6
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 5
- 229910052698 phosphorus Inorganic materials 0.000 description 5
- 239000011574 phosphorus Substances 0.000 description 5
- 230000008901 benefit Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910000679 solder Inorganic materials 0.000 description 3
- 229910000885 Dual-phase steel Inorganic materials 0.000 description 2
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- -1 zinc-aluminum-magnesium Chemical compound 0.000 description 2
- 208000012260 Accidental injury Diseases 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 230000009916 joint effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K11/00—Resistance welding; Severing by resistance heating
- B23K11/10—Spot welding; Stitch welding
- B23K11/11—Spot welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K11/00—Resistance welding; Severing by resistance heating
- B23K11/002—Resistance welding; Severing by resistance heating specially adapted for particular articles or work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K11/00—Resistance welding; Severing by resistance heating
- B23K11/30—Features relating to electrodes
Abstract
The invention relates to a spot welding process of a phosphorus-added high-strength galvanized aluminum-magnesium steel plate, belonging to the technical field of welding. When the steel plate is welded, a resistance spot welder is adopted for welding, the steel plate is pre-pressed through electrode pressure P1, and the pre-pressing time is t u Then for the first current I 1 Electrifying for t time w1 In ms, the cooling time is t c Then the electrode pressure P2 carries out a second current I 2 Electrifying for t time w2 The pressure maintaining time of the electrode pressure P2 after the power-on is finished is t H . By adopting the resistance spot welding method, the spot welding joint is prevented from generating cold joint and concave joint, the nugget diameter of each spot welding joint is larger than 4.5mm, the shearing resistance of each spot welding joint is larger than 7kN, the positive pulling performance is larger than 5kN, the shearing resistance and the positive pulling performance are better, and the welding effect is good。
Description
Technical Field
The invention belongs to the technical field of welding, and particularly relates to a spot welding process of a phosphorus-added high-strength galvanized aluminum magnesium steel plate.
Background
The light weight is a requirement of 'weight reduction and energy saving' of automobiles, and the high-strength steel plate can not only realize the light weight of automobiles, but also improve the passive safety of automobiles, so that the high-strength steel plate is increasingly used on automobiles. The high-strength steel with phosphorus is characterized in that a certain amount of phosphorus is particularly added into low-carbon steel or ultra-low-carbon steel, the strength of the steel is improved by utilizing the solid strengthening effect of the phosphorus, the thickness of the stamping part of the automobile can be properly reduced by using the steel plate, the dead weight of the automobile can be reduced, and good economic benefit is obtained. The method can be used for manufacturing outer covering parts such as a car door outer plate, an engine cover plate, a top cover and the like, and also can be used for manufacturing reinforcing parts such as a cross beam, a longitudinal beam and the like and structural parts. The resistance spot welding is the most commonly used welding method in the white car body manufacturing process because of the characteristics of high production efficiency, easy automation and the like. The safety of the vehicle body is directly affected by the quality of the spot welding performance, the resistance spot welding is a method of applying pressure to the combined weldment through an electrode and welding by utilizing resistance heat generated by current passing through the contact surface and the adjacent area of the joint, and the high strength of the phosphorus-added high-strength steel is mainly due to the solid solution strengthening effect of phosphorus elements added in the steel, and the defects of cold welding, surface dent and the like easily occur in the spot welding joint due to the high phosphorus content.
The Chinese patent publication No. CN114850644A discloses a resistance spot welding method of a 2000 MPa-grade hot formed steel plate, and relates to a high-strength steel plate spot welding process.
The chinese patent of publication No. CN106363288A discloses a resistance spot welding process for improving the quality of dual-phase steel welding spots, and performs spot welding by adopting a preheating-heating-cooling crystallization-tempering mode, so as to avoid the influence of molten metal splashing in the welding process on the welding quality and the possibility of accidental injury to human body, and the welding spots are stable in the welding process, reduce welding deformation, change brittle tissues, improve the quality of the welding spots, avoid shrinkage cavity and crack of the welding spots, and improve the quality of products.
In summary, most of the patents related to spot welding are dual-phase steel or high-strength steel as parent materials, and most of the patents related to the phosphorus-added high-strength zinc-aluminum-magnesium plating plate are focused on plating components and production thereof, and do not relate to welding process parameters to reduce cost and improve welding quality.
Disclosure of Invention
The invention solves the technical problem of providing a resistance spot welding method between spot welding processes of a phosphorus-added high-strength galvanized aluminum-magnesium steel plate. The invention solves the problems of spot welding cold joint and welding spot surface depression of the phosphorus-added high-strength galvanized aluminum magnesium steel plate by a variable pressure two-pulse process method and a self-made electrode cap.
In order to solve the technical problems, the invention adopts the following technical scheme: a spot welding process for a phosphorus-added high-strength galvanized aluminum-magnesium steel plate comprises the steps of welding the steel plate by adopting a resistance spot welder, and prepressing the steel plate through electrode pressure P1 for t time u Then for the first current I 1 Electrifying for t time w1 In ms, the cooling time is t c Then the electrode pressure P2 carries out a second current I 2 Electrifying for t time w2 The pressure maintaining time of the electrode pressure P2 after the power-on is finished is t H The electrode pressure unit is kN, and t is u 、t c 、t w1 、t w2 、t H In ms, and the current in kA.
Further, the specific steps of the process are as follows:
(1) Prepressing: pre-pressing the steel plate through electrode pressure P1, P1: 1.5-2.5 kN, and the pre-pressing time is t u =200～300ms；
(2) Welding current 1: electrode pressure P1: 1.5-2.5 kN, welding current I 1 =(0.5～0.6) I 2 Welding time t w1 =100～200ms；
(3) Welding current 2: electrode pressure was P2: 2.6-3.6 kN, welding current I 2 =I F -0.2, welding time t w2 =200 to 320ms, said I F The minimum current for generating welding spatter during single-pulse spot welding is used as the spatter current, and the unit is kA;
(4) Holding t after the welding current is stopped H= 20～40ms。
Further, the thickness of the steel plate is 1.2-1.6 mm.
Furthermore, in the whole process of the technology, an intermediate frequency inverter resistance welder is adopted, and the pressure of a variable electrode is adopted; after welding in the step (2), the cooling time is t c =20～40ms。
Further, the substrate steel plate of the phosphorus-added high-strength galvanized aluminum magnesium steel plate is HC220YD+ZM, the chemical components of the steel plate are less than or equal to 0.003% by mass, and Si:0.05 to 0.18 percent, mn:0.20 to 0.30 percent, P: 0.040-0.060%, S is less than or equal to 0.02%, als:0.030 to 0.050 percent, ti:0.035 to 0.060 percent, nb: 0.02-0.04%, and the balance of Fe and unavoidable impurity elements.
Further, the plating layer of the phosphorus-added high-strength galvanized aluminum magnesium steel plate comprises the following components: 1.5 to 2.0 percent, mg:1.0 to 1.5 percent of Zn and the balance of Zn, and the thickness of the plating layer is 80 to 160g/m 2 。
Further, the spot welding process adopts a self-made electrode cap, and the electrode material is Cr-Zr-Cu, wherein Cr:0.5 to 1.0 percent, zr:0.5 to 0.8 percent and the balance of Cu; the body of the electrode is cylindrical, the head is in a shape of a circular truncated cone, the diameter of the cambered surface of the top surface of the circular truncated cone is R50, the diameter is 5.0-5.5 mm, and the included angle between the top edge and the side edge of the circular truncated cone is 145 degrees on the section passing through the central axis of the circular truncated cone.
Further, the nugget diameter of the spot welding joint of the steel plate is more than 4.5mm, the shearing resistance of the spot welding joint is more than 7kN, and the forward pulling property of the spot welding joint is more than 5kN.
The beneficial effects of adopting above-mentioned technical scheme to produce lie in: by adopting the resistance spot welding method, the variable pressure two-pulse process method and the self-made electrode cap, the diameter of each spot welding joint nugget is more than 4.5mm, the spot welding joint nugget meets the standard requirement, the shearing resistance of each spot welding joint is more than 7kN, the positive pulling performance is more than 5kN, the shearing resistance and the positive pulling performance are better, and the welding effect is good. The variable pressure two-pulse process method and the self-made electrode cap improve the quality of welding spots, and the resistance spot welding method has the advantages of low production cost, short welding time, faster forming, high efficiency and high automation degree, and is beneficial to large-scale welding of the phosphorus-added high-strength steel plates.
Drawings
FIG. 1 is a schematic illustration of electrode cap dimensions of an embodiment of the invention;
FIG. 2 is a diagram of a resistance spot welding process of the present invention;
FIG. 3 is a low-power diagram of a cold joint caused by unreasonable process;
FIG. 4 is a low-power diagram of a solder joint depression caused by unreasonable process;
FIG. 5 is a low-power view of the solder joint of example 1.
Description of the embodiments
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The invention is illustrated by taking a phosphorus-added high-strength galvanized aluminum magnesium steel plate as an example, the brand of the steel plate is HC220YD+ZM, the chemical components of the steel plate are C less than or equal to 0.003 percent, and the mass percent of Si is as follows: 0.05 to 0.18 percent, mn:0.20 to 0.30 percent, P: 0.040-0.060%, S is less than or equal to 0.02%, als:0.030 to 0.050 percent, ti:0.035 to 0.060 percent, nb:0.02 to 0.04 percent, the balance being Fe and unavoidable impurity elements, the plating layer comprises the following components: 1.5 to 2.0 percent, mg:1.0 to 1.5 percent of Zn and the balance of Zn, and the thickness of the plating layer is 80 to 160g/m 2 。
The model of the medium-frequency inversion direct-current resistance spot welder is DB220, and the medium-frequency inversion direct-current resistance spot welder comprises a SIV31C type spot welding controller, an SP-255-FU10KN pressurizing force sensor test electrode pressure and an MM-316A welding detector test current, so that the welding effect is ensured.
A spot welding process for a phosphorus-added high-strength galvanized aluminum-magnesium steel plate adopts an intermediate frequency inverter resistance welder and adopts variable electrode pressure, and comprises the following specific steps:
when the HC220YD+ZM steel plates are welded, a resistance spot welder is used for welding, the welder adopts an intermediate frequency inversion direct current resistance spot welder of the model DB220, an electrode cap is self-made, and the electrode material is Cr-Zr-Cu, wherein Cr:0.5 to 1.0 percent, zr:0.5 to 0.8 percent and the balance of Cu; the body of the electrode is cylindrical, the head is in a shape of a circular truncated cone, the diameter of the cambered surface of the top surface of the circular truncated cone is R50, the diameter is 5.0-5.5 mm, and the included angle between the top edge and the side edge of the circular truncated cone is 145 degrees on the section passing through the central axis of the circular truncated cone.
(1) Prepressing: pre-pressing the steel plate through electrode pressure P1, P1: 1.5-2.5 kN, and the pre-pressing time is t u =200 to 300ms; the thickness of the steel plate is 1.2-1.6 mm;
the plating layer of the phosphorus-added high-strength zinc-aluminum-magnesium plated steel plate comprises the following components: 1.5 to 2.0%, mg:1.0 to 1.5 percent of Zn and the balance of Zn, and the thickness of the plating layer is 80 to 160g/m 2 ；
(2) Welding current 1: electrode pressure P1: 1.5-2.5 kN, welding current I 1 =(0.5～0.6) I 2 Welding time t w1 =100 to 200ms, cooling time t c =20～40ms；
(3) Welding current 2: electrode pressure was P2: 2.6-3.6 kN, welding current I 2 =I F -0.2, welding time t w2 =200 to 320ms, said I F The minimum current for generating welding spatter during single-pulse spot welding is used as the spatter current, and the unit is kA;
(4) Holding t after the welding current is stopped H= 20～40ms。
The control parameters of examples 1-6 are shown in Table 1, the properties of the obtained welding spots are shown in Table 2, the chemical compositions and thicknesses of the steel plate substrate, the plating layer are shown in Table 3, the nugget diameter of the steel plate spot welding joint is more than 4.5mm, the shearing resistance of the spot welding joint is more than 7kN, and the positive drawability of the spot welding joint is more than 5kN.
Table 1 examples 1-6 welding process control parameters
After welding, the nugget diameter of each spot welding joint and the shearing resistance of the spot welding joint were measured, and the measurement results are shown in Table 2.
Table 2 examples 1-6 solder joint properties
TABLE 3 examples 1-6 Steel sheet substrates, plating chemical composition and thickness
The above embodiments are only for illustrating the technical solution of the present invention, and it should be understood by those skilled in the art that although the present invention has been described in detail with reference to the above embodiments: modifications and equivalents may be made thereto without departing from the spirit and scope of the invention, which is intended to be encompassed by the claims.
Claims (8)
1. A spot welding process for a phosphorus-added high-strength galvanized aluminum-magnesium steel plate is characterized in that a resistance spot welder is adopted for welding when the steel plate is welded, the steel plate is pre-pressed through electrode pressure P1, and the pre-pressing time is t u Then for the first current I 1 Electrifying for t time w1 In ms, the cooling time is t c Then the electrode pressure P2 carries out a second current I 2 Electrifying for t time w2 The pressure maintaining time of the electrode pressure P2 after the power-on is finished is t H The electrode pressure unit is kN, and t is u 、t c 、t w1 、t w2 、t H In ms, and the current in kA.
2. The spot welding process for the phosphorus-added high-strength galvanized aluminum magnesium steel plate according to claim 1, which is characterized by comprising the following specific steps:
(1) Prepressing: pre-pressing the steel plate through electrode pressure P1, P1: 1.5-2.5 kN, and the pre-pressing time is t u =200～300ms；
(2) Welding current 1: electrode pressure P1: 1.5-2.5 kN, welding current I 1 =(0.5～0.6) I 2 Welding time t w1 =100～200ms；
(3) Welding current 2: electrode pressure was P2: 2.6-3.6 kN, welding current I 2 =I F -0.2, welding time t w2 =200 to 320ms, said I F The minimum current for generating welding spatter during single-pulse spot welding is used as the spatter current, and the unit is kA;
(4) Holding t after the welding current is stopped H= 20～40ms。
3. The spot welding process for the phosphorus-added high-strength galvanized aluminum magnesium steel plate according to claim 1, wherein the thickness of the steel plate is 1.2-1.6 mm.
4. The spot welding process of the phosphorus-added high-strength galvanized aluminum-magnesium steel plate, which is characterized in that an intermediate frequency inverter resistance welder is adopted in the whole process, and a variable electrode pressure is adopted; after welding in the step (2), the cooling time is t c =20～40ms。
5. The spot welding process for the phosphorus-added high-strength galvanized aluminum magnesium steel sheet according to any one of claims 1 to 4, wherein the steel sheet of the phosphorus-added high-strength galvanized aluminum magnesium steel sheet is characterized in that the steel sheet of the substrate is of the brand HC220YD+ZM, the steel sheet chemical composition and the mass percentage content thereof are C less than or equal to 0.003 percent, si:0.05 to 0.18 percent, mn:0.20 to 0.30 percent, P: 0.040-0.060%, S is less than or equal to 0.02%, als:0.030 to 0.050 percent, ti:0.035 to 0.060 percent, nb: 0.02-0.04%, and the balance of Fe and unavoidable impurity elements.
6. The spot welding process for a phosphorus-added high-strength galvanized aluminum magnesium steel sheet according to any one of claims 1 to 4, wherein the plating composition of the phosphorus-added high-strength galvanized aluminum magnesium steel sheet is as follows: 1.5 to 2.0 percent, mg:1.0 to 1.5 percent of Zn and the balance of Zn, and the thickness of the plating layer is 80 to 160g/m 2 。
7. The spot welding process of the phosphorus-added high-strength galvanized aluminum magnesium steel sheet according to any one of claims 1 to 4, wherein the spot welding process adopts a self-made electrode cap, the electrode material is Cr-Zr-Cu, and Cr:0.5 to 1.0 percent, zr:0.5 to 0.8 percent and the balance of Cu; the body of the electrode is cylindrical, the head is in a shape of a circular truncated cone, the diameter of the cambered surface of the top surface of the circular truncated cone is R50, the diameter is 5.0-5.5 mm, and the included angle between the top edge and the side edge of the circular truncated cone is 145 degrees on the section passing through the central axis of the circular truncated cone.
8. The spot welding process for the phosphorus-added high-strength galvanized aluminum-magnesium steel sheet according to any one of claims 1 to 4, wherein the diameter of a nugget of a spot welding joint of the steel sheet is more than 4.5mm, the shearing resistance of the spot welding joint is more than 7kN, and the positive drawability of the spot welding joint is more than 5kN.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310599355 | 2023-05-25 | ||
| CN2023105993556 | 2023-05-25 |
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| Publication Number | Publication Date |
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| CN116944645A true CN116944645A (en) | 2023-10-27 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310972988.7A Pending CN116944645A (en) | 2023-05-25 | 2023-08-04 | Spot welding process for phosphorus-added high-strength galvanized aluminum-magnesium steel plate |
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- 2023-08-04 CN CN202310972988.7A patent/CN116944645A/en active Pending
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