Electric arc welding process of multi-metal gradient structure

Abstract

The invention provides an electric arc welding process of a multi-metal gradient structure, which comprises the following steps: S1, preparing at least two different metal materials, and carrying out pretreatment according to gradient structure requirements; s2, the metal materials are stacked and positioned, and it is ensured that welding areas are accurately aligned; s3, setting welding parameters including welding current, voltage, welding speed and protective gas type and flow; s4, pulse electric arc welding is adopted, and the metal materials are welded in a gradual transition mode; s5, stress relief annealing and surface treatment are conducted on the welded structure; through a special welding process, gradual change of metal components at a welding joint is realized, so that the mechanical property and the corrosion resistance of the welding joint are improved.

Description

Technical Field

[0001] The invention relates to the technical field of material welding, and in particular to an arc welding process for a multi-metal gradient structure. Background Art

[0002] Composite materials have the beneficial properties of multiple materials. Therefore, they are widely used in many processing and manufacturing occasions, especially in some casting components. However, since composite materials have two or more different materials, it is very difficult to weld them. At present, solid phase welding or melting welding is usually used for welding composite materials with multi-metal gradient structures. However, there are still certain shortcomings in the process of welding different materials. For example, for a multi-metal gradient structure composed of aluminum alloy and stainless steel materials, it is difficult to weld them using the current common welding methods due to different properties and melting points.

[0003] Therefore, a new technical solution is urgently needed to solve the above-mentioned technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a welding process for a multi-metal gradient structure, which adopts the following technical solutions: An arc welding process for a multi-metal gradient structure, the process comprising the following steps: S1. Prepare at least two different metal materials and pre-treat them according to the gradient structure requirements; S2, stacking and positioning the metal materials to ensure accurate alignment of the welding areas; S3. Set welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate; S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Perform stress relief annealing and surface treatment on the welded structure; The welding parameter settings include: - Welding current: 100-250A; - Welding voltage: 15-30V; - Welding speed: 10-30cm / min; - Shielding gas flow rate: argon 12-15L / min, carbon dioxide 0-5L / min.

[0005] Furthermore, the different metal materials include aluminum alloy and stainless steel.

[0006] Furthermore, the pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

[0007] Furthermore, in step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 1-5 Hz and the pulse width is 30-70%.

[0008] Further, in step S1, the preprocessing includes: Grinding and roughening the surfaces of at least two different metal materials; Preheat at least two different metal materials at 300-350°C, keep them warm for 20-30 minutes, and cool them naturally to 100-150°C.

[0009] Furthermore, in step S2, during the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 150-200°C.

[0010] Further, in step S5, the stress annealing includes: Heat the welded structure to 300-350℃ within 30-40 minutes and keep it warm for 20-30 minutes; The welded structure is then reheated to 400-450°C and kept warm for 20-30 min, then cooled to room temperature.

[0011] The beneficial effects produced by the present invention are as follows: The welding process provided by this embodiment has the following advantages compared with the prior art: Gradient metal composition: Through special welding process, the gradual change of metal composition at the weld joint is achieved, thereby improving the mechanical properties and corrosion resistance of the weld joint.

[0012] Reduce heat-affected zone: Optimized welding parameters and process settings reduce the size of the heat-affected zone and alleviate welding stress concentration.

[0013] Improved stress distribution: Through the design of multi-metal gradient structure, the stress distribution at the welded joint is optimized and the overall performance of the welded structure is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a welding process flow chart of the present invention. DETAILED DESCRIPTION

[0015] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with the embodiments and drawings, and the contents mentioned in the embodiments are not intended to limit the present invention. The present invention is described in detail below in conjunction with the drawings.

[0016] See also Figure 1 , which is a process flow chart of arc welding of a multi-metal gradient structure according to the present invention.

[0017] In this embodiment, the present invention provides an arc welding process for a multi-metal gradient structure, the process comprising the following steps: S1. Prepare at least two different metal materials and pre-treat them according to the gradient structure requirements; S2, stacking and positioning the metal materials to ensure accurate alignment of the welding areas; S3. Setting welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate; S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Perform stress relief annealing and surface treatment on the welded structure; The welding parameter settings include: - Welding current: 100-250A; - Welding voltage: 15-30V; - Welding speed: 10-30cm / min; - Shielding gas flow rate: argon 12-15L / min, carbon dioxide 0-5L / min.

[0018] In this embodiment, the different metal materials include aluminum alloy and stainless steel.

[0019] In this embodiment, the pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

[0020] In this embodiment, in step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 1-5 Hz, and the pulse width is 30-70%.

[0021] In this embodiment, in step S1, the preprocessing includes: Grinding and roughening the surfaces of at least two different metal materials; Preheat at least two different metal materials at 300-350°C, keep them warm for 20-30 minutes, and cool them naturally to 100-150°C.

[0022] In this embodiment, in step S2, during the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 150-200°C.

[0023] In this embodiment, in step S5, the stress annealing includes: Heat the welded structure to 300-350℃ within 30-40 minutes and keep it warm for 20-30 minutes; The welded structure is then reheated to 400-450°C and kept warm for 20-30 min, then cooled to room temperature.

[0024] Embodiment 1 In this embodiment, the process of arc welding the multi-metal gradient structure includes the following steps: S1. Prepare at least two different metal materials and perform pretreatment according to the requirements of the gradient structure. In this step, the surfaces of at least two different metal materials are polished and roughened, and then at least two different metal materials are preheated in advance at a preheating temperature of 350°C. After keeping the temperature for 30 minutes, they are naturally cooled to 150°C.

[0025] S2, stacking and positioning the metal materials. In the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 200° C., and the welding areas are precisely aligned during stacking; S3. Set welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate; the specific parameters are: - Welding current: 100A; - Welding voltage: 15V; - Welding speed: 10cm / min; - Shielding gas flow rate: argon 12L / min; S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Stress relief annealing and surface treatment are performed on the welded structure. In this step, the annealing process includes heating the welded structure to 350°C within 40 minutes and keeping it warm for 30 minutes. Then, the welded structure is reheated to 450°C and kept warm for 30 minutes, and then naturally cooled to room temperature.

[0026] In this embodiment, the pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

[0027] In this embodiment, in step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 1 Hz and the pulse width is 30%.

[0028] The welding process provided by this embodiment has the following advantages compared with the prior art: Gradient metal composition: Through special welding process, the gradual change of metal composition at the weld joint is achieved, thereby improving the mechanical properties and corrosion resistance of the weld joint.

[0029] Reduce heat-affected zone: Optimized welding parameters and process settings reduce the size of the heat-affected zone and alleviate welding stress concentration.

[0030] Improved stress distribution: Through the design of multi-metal gradient structure, the stress distribution at the welded joint is optimized and the overall performance of the welded structure is improved.

[0031] Embodiment 2 In this embodiment, the process of arc welding the multi-metal gradient structure includes the following steps: S1. Prepare at least two different metal materials and perform pretreatment according to the requirements of the gradient structure. In this step, the surfaces of at least two different metal materials are polished and roughened, and then at least two different metal materials are preheated in advance at a preheating temperature of 300°C. After keeping the temperature for 20 minutes, they are naturally cooled to 100°C.

[0032] S2, stacking and positioning the metal materials. In the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 150° C., and the welding areas are precisely aligned during stacking; S3. Set welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate. Specific parameter settings include: - Welding current: 250A; - Welding voltage: 30V; - Welding speed: 0cm / min; - Shielding gas flow: argon 15L / min, carbon dioxide 5L / min; S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Perform stress relief annealing and surface treatment on the welded structure; The annealing process includes heating the welded structure to 300°C within 30 minutes and keeping it warm for 20 minutes; then heating the welded structure to 400°C for a second time and keeping it warm for 20 minutes, and then naturally cooling it to room temperature.

[0033] In this embodiment, the pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

[0034] In this embodiment, in step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 5 Hz and the pulse width is 70%.

[0035] Embodiment 3 In this embodiment, the process of arc welding the multi-metal gradient structure includes the following steps: S1. Prepare at least two different metal materials and perform pretreatment according to the requirements of the gradient structure. In this step, the surfaces of at least two different metal materials are polished and roughened, and then at least two different metal materials are preheated in advance at a preheating temperature of 330° C., and are kept warm for 250 min and then naturally cooled to 150° C.

[0036] S2, stacking and positioning the metal materials. In the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 200° C., and the welding areas are precisely aligned during stacking; S3. Setting welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate; The welding parameter settings include: - Welding current: 200A; - Welding voltage: 20V; - Welding speed: 25cm / min; - Shielding gas flow: argon 14L / min, carbon dioxide 3L / min.

[0037] S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Perform stress relief annealing and surface treatment on the welded structure; The annealing process includes heating the welded structure to 350°C within 35 minutes and keeping it warm for 25 minutes; then heating the welded structure to 430°C for a second time and keeping it warm for 25 minutes, and then naturally cooling it to room temperature.

[0038] In this embodiment, the pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

[0039] In this embodiment, in step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 35 Hz and the pulse width is 70%.

[0040] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in any form. Although the present invention is disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technology of the present invention, which do not depart from the content of the technical solution of the present invention, are within the scope of the technical solution of the present invention.

Claims

1. An arc welding process of a multi-metal gradient structure, characterized in that: The process includes the following steps: S1. Prepare at least two different metal materials and pre-treat them according to the gradient structure requirements; S2, stacking and positioning the metal materials to ensure accurate alignment of the welding areas; S3. Set welding parameters, including welding current, voltage, welding speed, and shielding gas type and flow rate; S4, using pulse arc welding to weld the metal materials in a gradual transition manner; S5. Perform stress relief annealing and surface treatment on the welded structure; The welding parameter settings include: - Welding current: 100-250A; - Welding voltage: 15-30V; - Welding speed: 10-30cm / min; - Shielding gas flow rate: argon 12-15L / min, carbon dioxide 0-5L / min.

2. The arc welding process of a multi-metal gradient structure according to claim 1, characterized in that: The different metal materials include aluminum alloy and stainless steel.

3. The arc welding process of a multi-metal gradient structure according to claim 1, characterized in that: The pulse arc welding uses the pulse frequency and width of the arc current to control the penetration depth and the mixing of the molten pool.

4. The arc welding process of a multi-metal gradient structure according to claim 3, characterized in that: In step S3, the setting of the welding parameters also includes the frequency and width of the pulse current, wherein the pulse current frequency is 1-5 Hz and the pulse width is 30-70%.

5. The arc welding process of a multi-metal gradient structure according to claim 1, characterized in that: In step S1, the preprocessing includes: Grinding and roughening the surfaces of at least two different metal materials; Preheat at least two different metal materials at 300-350℃, keep them warm for 20-30 minutes, and cool them naturally to 100-150℃.

6. The arc welding process for metal gradient structure according to claim 1, characterized in that: In step S2, during the process of stacking and positioning the two metal materials, the surfaces to be welded of the two metal materials are pressed against each other and rubbed against each other, so that the temperature of the surfaces to be welded rises to 150-200°C.

7. The arc welding process of a multi-metal gradient structure according to claim 1, characterized in that: In step S5, the stress annealing includes: Heat the welded structure to 300-350℃ within 30-40 minutes and keep it warm for 20-30 minutes; The welded structure is then reheated to 400-450°C and kept warm for 20-30 min, then cooled to room temperature.

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