High-Strength Ultrafine-Grained Al-Mg-Si Alloys Exposed to Mechanical Alloying and Press-Forming: A Comparison with Cast Alloys

Wenjie Zhong; Lin Song; Huaguo Tang; Xu Wu; Zhuhui Qiao; Xunyong Liu

doi:10.3390/ma18010099

High-Strength Ultrafine-Grained Al-Mg-Si Alloys Exposed to Mechanical Alloying and Press-Forming: A Comparison with Cast Alloys

Materials (Basel). 2024 Dec 29;18(1):99. doi: 10.3390/ma18010099.

Authors

Wenjie Zhong^{1

2}, Lin Song¹, Huaguo Tang^{1

3

4}, Xu Wu^{1

5}, Zhuhui Qiao^{1

3

4}, Xunyong Liu^{1

2}

Affiliations

¹ Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai, Yantai 264006, China.
² School of Chemistry and Materials Science, Ludong University, Yantai 264025, China.
³ Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering, Yantai 264006, China.
⁴ State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
⁵ Yantai Huihua Metal Sci. & Tech. Co., Ltd., Yantai 264006, China.

Abstract

A high-strength Al-Mg-Si alloy was prepared using mechanical alloying (MA) combined with press-forming (PF) technology, achieving a strength of up to 715 MPa and a hardness of 173 HB. The microstructures were comparatively analyzed with conventional cast Al-Mg-Si alloys using XRD, TKD, and TEM. The XRD results showed that the full width at half maximum (FWHM) of the alloy prepared by MA+PF was significantly broadened and accompanied by a shift in the diffraction peak. TKD revealed that the grain size of the MA+PF processed alloy was significantly reduced to approximately 260 nm, indicating substantial refinement compared to the cast alloy. Additionally, using TEM, it was found that the newly developed MA+PF alloy exhibited a distinct morphology of Mg₂Si precipitation phases and a high density of stacking faults (SFs), characteristics that differed from those in the cast alloy. The significant enhancement in strength can be attributed to the synergistic strengthening effects of grain refinement, second-phase precipitation, and stacking fault strengthening, as synthesized and analyzed.

Keywords: Al-Mg-Si alloys; grain refinement; high strength; mechanical alloying; press-forming; stacking faults.

Grants and funding

This work was supported by the Shandong Provincial Natural Science Foundation (ZR2020ZD29 and ZR2021JQ20) and the Program of Shandong Laboratory (SYS202204); the National Key Technology R&D Program of China (no. 2022YFB3706204); the Key R&D Program of Shandong Province, China (2024CXGC010316); and the Taishan Scholars Program of Shandong Province.