CN-118028669-B - High-performance aluminum alloy for additive manufacturing and preparation method thereof

Abstract

Aiming at the problem of cracking in additive manufacturing of aluminum alloy, the invention provides a component design thought and a preparation method of high-performance aluminum alloy for additive manufacturing, and enriches an aluminum alloy material system in additive manufacturing. The 2000 or 7000 series high-strength aluminum alloy is combined with a proper amount of Y element and transition group metal elements such as Sc, zr, ti and the like, so that the cracking sensitivity is reduced, the cracking problem of additive manufacturing is solved, the forming performance of the additive manufacturing is improved, and the additive manufacturing is more suitable for additive manufacturing. The high-performance aluminum alloy for additive manufacturing provided by the invention has good additive manufacturing forming performance, can be prepared into crack-free aluminum alloy within a wider technological parameter range, and has excellent comprehensive mechanical properties. The invention has reasonable component design, simple preparation process, excellent performance of the obtained product, wide range of additive manufacturing process parameters and convenient large-scale industrial production and practical application.

Inventors

• LIU ZUMING
• LIU TAO
• Jiang Daoyan
• YE SHUPENG
• ZHANG YAZHOU
• ZHOU RUNXING
• CHEN LEI

Assignees

• 中南大学

Dates

Publication Date

20260512

Application Date

20240117

Claims (4)

1. 1. A preparation method of a high-performance aluminum alloy for additive manufacturing is characterized in that the high-performance aluminum alloy is 2000 series aluminum alloy, rare earth Y and transition group metal elements are simultaneously introduced, wherein the transition group metal elements are at least one of Sc, zr and Ti elements, and the 2000 series aluminum alloy is 2A14 aluminum alloy; the aluminum alloy powder comprises the following components in percentage by mass: 4.0-4.9% of Cu, 1.0-3% of Y, 0.4-1.8% of Mg, 0.4-1.2% of Si, 0.4-1.0% of Mn, 0.5% of Fe, 0.6-1.5% of transition group metal element and the balance of Al, wherein the transition group metal element is selected from at least one of Sc, zr and Ti elements; the high-performance aluminum alloy is prepared by adopting an additive manufacturing method by taking aluminum alloy powder as a raw material, so as to obtain the printing-state crack-free aluminum alloy; Preheating a substrate before additive manufacturing, wherein the preheating temperature is 80-200 ℃; the laser power of laser additive manufacturing is 200-400W, the scanning speed is 300-1500 mm/s, the lap joint interval is 80-150 mu m, the layer thickness is 30-50 mu m, and the interlayer rotation angle is 65-70 degrees; the additive manufacturing process adopts a protective atmosphere, and the oxygen content in a forming bin is controlled to be less than 0.1 wt percent; The protective gas is one of nitrogen, argon and helium, or a mixed gas of nitrogen, argon and helium, the purity is more than 99.99 wt percent, and the oxygen content is less than 0.0001 percent wt percent; When the prepared printing state product is Al-4.2Cu-0.5Mg-1.1Si-0.7Mn-1.3Y-0.7Zr (weight percent, wt.%) alloy, the yield strength is more than or equal to 318 MPa, the tensile strength is more than or equal to 418 MPa, the elongation is more than 13.8%, and no crack defect exists.
2. 2. The method for preparing the high-performance aluminum alloy for additive manufacturing according to claim 1, wherein the aluminum alloy powder is placed in a vacuum drying oven for drying treatment, the heat preservation temperature is 80-120 ℃, and the treatment time is 2-12 hours.
3. 3. The method of claim 1, wherein the additive manufacturing technique is one of laser powder bed melting, electron beam melting or coaxial powder feeding laser forming.
4. 4. The method of manufacturing a high performance aluminum alloy for additive manufacturing according to claim 3, wherein the additive manufacturing technique is laser powder bed melting.

Description

High-performance aluminum alloy for additive manufacturing and preparation method thereof Technical Field The invention relates to a high-performance aluminum alloy for additive manufacturing and a preparation method thereof, belonging to the field of aluminum alloy and additive manufacturing. Background The aluminum alloy has excellent mechanical properties and high specific strength, and is widely applied to aerospace structural members. The additive manufacturing technology has high design freedom and unique advantages in the aspect of preparing the aluminum alloy complex-shaped member. The cooling rate and the temperature gradient of the additive manufacturing are high, the traditional high-strength aluminum alloy designed based on the casting-deforming processing process is easy to generate additive manufacturing cracking, the forming difficulty is high, and ideal microstructure and mechanical property are difficult to obtain. Therefore, there is a need to develop high performance aluminum alloys suitable for additive manufacturing fabrication processes. LI et al [LI,et al.Laserpowderbedfusion ofnano-titaniamodified2219 aluminiumalloywith superior mechanical properties atboth room and elevatedtemperatures:The significant impact ofsolute[J].Additive Manufacturing,2022,60:103296] discloses a TiO 2 modified 2219 aluminum alloy, which is almost completely dense, has a yield strength of 173MPa, a tensile strength of 366MPa, and an elongation of 11.1% by laser powder bed melting (LPBF). CHEN et Al [CHEN et al.Microstructure characterization and mechanical properties ofcrack-free Al-Cu-Mg-Yalloy fabricated by laser powder bed fusion,Additive Manufacturing,2022,58:103006] A2024/Y mixed powder was prepared by adding 1.5wt% Y to 2024 aluminum alloy powder, and a novel high strength Al-Cu-Mg-Y alloy without cracking was prepared by LPBF. The yield strength of the printed sample was 206MPa, the tensile strength was 259MPa, and the elongation was 3%. ZHANG et Al [ZHANGH,et al.Effect ofZirconium addition on crack,microstructure and mechanical behavior ofselective laser melted Al-Cu-Mg alloy[J].Scripta Materialia,2017,134:6-10] discloses a Zr (2 wt%) modified Al-Cu-Mg alloy, wherein the elongation of the Al-Cu-Mg-Zr alloy prepared by LPBF is reduced by 55% compared with that of the Al-Cu-Mg alloy. ZHANG et Al [ZHANG J,et al.A novel crack-free Ti-modified Al-Cu-Mg alloy designed for selective laser melting[J].Additive Manufacturing,2021,38:101829] discloses a novel crack-free Ti (1.5 wt%) modified Al-Cu-Mg alloy for LPBF, with a printed alloy yield strength of 293MPa, tensile strength of 426MPa, and elongation of 9.1%. The invention provides a component design thought of a high-performance aluminum alloy for additive manufacturing, which improves the additive manufacturing forming performance of 2000 or 7000 series aluminum alloy by combining Y element and transition group metal element, solves the cracking problem of additive manufacturing, widens the forming process window and designs the high-performance aluminum alloy suitable for additive manufacturing. Disclosure of Invention The invention provides a high-performance aluminum alloy for additive manufacturing and a preparation method thereof, aiming at solving the problem of poor formability and manufacturability of the additive manufacturing of the aluminum alloy. The high-performance aluminum alloy for additive manufacturing provided by the invention can adapt to the high temperature gradient and cooling rate of an additive manufacturing process, does not crack in the forming process, and the prepared product has excellent mechanical properties. In order to achieve the above object, the present invention provides a high-performance aluminum alloy for additive manufacturing, in which rare earth Y and a transition group metal element are simultaneously introduced into 2000 or 7000 series aluminum alloy; The transition metal element is at least one selected from Sc, zr and Ti. The invention provides a preparation method of high-performance aluminum alloy for additive manufacturing, which is characterized in that aluminum alloy powder is used as a raw material, and printing-state crack-free aluminum alloy is obtained by additive manufacturing. The invention relates to a high-performance aluminum alloy for additive manufacturing and a preparation method thereof, wherein the aluminum alloy powder comprises the following components in percentage by mass: 4.0-4.9% of Cu, 1.0-3.0% of Y, 0.4-1.8% of Mg, 0.4-1.2% of Si, 0.4-1.0% of Mn, 0.6-1.5% of Fe, 0.6-1.5% of transition metal element and the balance of Al. The aluminum alloy powder is prepared by adopting an air atomization method. Preferably, the mass ratio of Y to the transition metal element is 1.2 to 1.4:0.8 to 0.6. According to the preparation method of the high-performance aluminum alloy for additive manufacturing, the aluminum alloy powder is placed in a vacuum drying oven for drying treatment, the heat preserv