CN-119077129-B - Aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method

Abstract

The invention discloses an aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method, which belongs to the technical field of welding and comprises the following steps of (1) preparing composite powder, namely, preparing ceramic powder and high-entropy alloy powder according to a certain proportion, performing plasma spheroidization to obtain ceramic/high-entropy alloy composite powder, (2) performing pretreatment on a welding sample, namely, polishing the surface to be welded of an aluminum alloy plate to be welded and a 25mm area around a welding line to remove an oxide film, wiping the surface with a volatile organic solvent, putting the surface to be welded into a drying device to be dried, and (3) butt-jointing and placing the aluminum alloy plate in the step (2) and fixing the aluminum alloy plate through a pressing plate to form a structure to be welded, and (4) welding the structure to be welded in the step (3) by adopting a laser powder filling welding process. The invention uniformly distributes the ceramic/high-entropy alloy composite powder in the welding seam by virtue of the stirring effect of laser on the molten pool, has the advantages of ceramic particle reinforcement and high-entropy alloy particle reinforcement, and can effectively improve the strength of the welding seam joint.

Inventors

• ZHU DEZHI
• HUANG WENQIANG
• LI XIAOQIANG
• YANG CHAO
• CHEN SHUYU
• TANG ZELIN

Assignees

• 华南理工大学

Dates

Publication Date

20260505

Application Date

20240731

Claims (7)

1. 1. The aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method is characterized by comprising the following steps of (1) preparing composite powder, namely, performing plasma spheroidization on ceramic powder and high-entropy alloy powder according to a certain mass ratio to obtain ceramic/high-entropy alloy composite powder; the ceramic/high-entropy alloy composite powder comprises 1-50% of ceramic, 50-99% of high-entropy alloy, the sum of the ceramic powder and the high-entropy alloy is equal to 1, the ceramic powder is flaky or other irregular shapes and has the particle size of 0.05-1 mu m, the high-entropy alloy powder is spherical and has the particle size of 1-100 mu m, the ceramic/high-entropy alloy composite powder is spherical and has the particle size of 1-100 mu m, (2) the surface to be welded of an aluminum alloy plate to be welded and a 25mm area around a welding line are polished to remove an oxide film, the aluminum alloy plate is wiped clean by a volatile organic solvent and then is dried in a drying device, (3) the aluminum alloy plate in the step (2) is butted and fixed by a pressing plate to form a structure to be welded, (4) the structure to be welded is welded by adopting a laser powder filling welding process, the powder filling mode is a synchronous powder feeding method, the coaxial powder or a bypass powder feeding method, and high-purity argon gas with the mass concentration of not lower than 99.99% is adopted for coaxial protection during welding, and the gas flow is protected to be 10-15 min/L.
2. 2. The method for powder filling welding of aluminum alloy laser ceramic/high-entropy alloy composite powder according to claim 1, wherein in the step (1), the ceramic powder comprises TiB 2 , tiC, tiN, siC or ZrO 2 , and the high-entropy alloy powder comprises FeCoCrNi series, feCoCrNiMn series, feCoCrNiMo series, alCoCrFeNi series, alTiCrNiCu series, WTaMoNbV series or TiNbZrTa series.
3. 3. The aluminum alloy laser ceramic/high-entropy alloy composite powder filler metal welding method of claim 1, wherein in step (2), the aluminum alloy comprises a cast aluminum alloy and a wrought aluminum alloy, and the cast aluminum alloy comprises an Al-Si system, an Al-Cu system, an Al-Mg system or an Al-Zn system.
4. 4. The aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method according to claim 1, wherein in the step (2), the thickness of the aluminum alloy to be welded is 1-6mm.
5. 5. The aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method according to claim 4, wherein in the step (2), the aluminum alloy to be welded is not beveled when the thickness is 1-3mm, and is beveled when the thickness is 4-6mm, and the beveled shape comprises an I shape, a V shape or a Y shape.
6. 6. The method for powder filling welding of aluminum alloy laser ceramic/high-entropy alloy composite powder according to claim 1, wherein in the step (2), the volatile organic solvent comprises ethanol or acetone.
7. 7. The aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method according to claim 1, wherein in the step (2), the drying temperature is 60-80 ℃ and the drying time is 20-40min.

Description

Aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method Technical Field The invention relates to the technical field of welding, and particularly provides a powder filling welding method for aluminum alloy laser ceramic/high-entropy alloy composite powder. Background The aluminum alloy has the advantages of low density, excellent mechanical property, corrosion resistance and the like, and becomes a preferred light material for reducing the dead weight of a vehicle body and improving the fuel efficiency in the current automobile industry, especially in the new energy automobile industry. In the production and manufacturing process of the vehicle body and the parts, the connection problem is inevitably considered, so that how to realize high-efficiency and high-quality connection of the aluminum alloy has important significance for manufacturing the vehicle body. As an emerging welding technology, laser welding has received more and more attention in the field of aluminum alloy welding by virtue of the advantages of small welding deformation, small heat affected zone, wide processing range and the like. However, aluminum alloy has low absorptivity to laser light as a high-reflection material. In addition, the original fine tissues and nano precipitated phases in the base material cannot be reserved under the action of laser, so that a weld zone is obviously softened, and the strength of a welded joint is obviously reduced compared with that of the base material. The laser powder filling welding is to fill metal or nonmetal powder into a molten pool for material supplementation during welding. Compared with laser self-fusion welding, the method has the advantages of improved utilization rate, lower requirement on assembly precision, convenience in adjustment during welding, abundant types of fillable materials, easiness in controlling components, capability of meeting different application requirements, capability of obtaining more stable welding effect by adding active ingredients, improvement on weld formation, defect inhibition and improvement on mechanical properties of the joint. Currently, for aluminum alloy laser filling powder, single-substance powder or mixed powder thereof, such as Si powder, cu powder, zr powder, mn powder and the like, and partial ceramic particles are mostly adopted. For example, according to chinese patent (CN 108723596 a), tiB 2 particles are uniformly distributed in a weld seam by means of stirring action of laser on a molten pool, and the strength of a welded joint is remarkably improved based on the stability of ceramic particles in a laser welding process. The high-entropy alloy has excellent mechanical properties, and compared with a ceramic material, the high-entropy alloy has better wettability with an aluminum matrix and higher interface bonding strength. Currently, there are scholars trying to apply high entropy alloys in the welding field. For example, chinese patent (CN 101554685A) discloses a high-entropy alloy solder for welding copper and aluminum and a preparation method thereof. However, at present, the ceramic/high-entropy alloy composite powder is not reported as filler powder for aluminum alloy laser filler welding. In view of the above analysis, the present patent application proposes using ceramic/high-entropy alloy composite powder as a filler material for aluminum alloy laser filler welding, relying on the synergistic effect of ceramic powder and high-entropy alloy powder to improve the weld joint strength. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a powder filling welding method for aluminum alloy laser ceramic/high-entropy alloy composite powder. The technical scheme of the invention is as follows: an aluminum alloy laser ceramic/high-entropy alloy composite powder filling welding method comprises the following steps: (1) Preparing composite powder, namely, preparing ceramic powder and high-entropy alloy powder according to a certain proportion through plasma spheroidization to obtain ceramic/high-entropy alloy composite powder; (2) Polishing the surface to be welded of the aluminum alloy plate to be welded and a 25mm area around the welding seam to remove an oxide film, wiping the aluminum alloy plate to be welded with a volatile organic solvent, and then putting the aluminum alloy plate to be welded into drying equipment for drying; (3) Butt-jointing and placing the aluminum alloy plates in the step (2), and fixing the aluminum alloy plates through a pressing plate to form a structure to be welded; (4) And (3) welding the structure to be welded in the step (3) by adopting a laser powder filling welding process. In the above method, in the step (1), the ceramic powder includes TiB 2、TiC、TiN、SiC、ZrO2, etc., and the high-entropy alloy powder includes FeCoCrNi system, feCoCrNiMn system, feCoCrNiMo system, alCoCrFeNi system, alTiCrNiCu system, WTaMoNbV system, tiNbZrTa s