An Investigation on the Microstructure and Texture of an AZ80 Cup-Shaped Piece Processed by Rotating Backward Extrusion

Materials

Xin Che¹  Jin Ma¹  Mu Meng¹  Beibei Dong¹  Kai Liu¹  Zhimin Zhang¹  Fulai Yang¹  Qiang Wang¹  Zhi Gao¹ 

[1] College of Materials Science and Engineering, North University of China, Taiyuan 030051, China;

关键词: AZ80 magnesium alloy;    rotating backward extrusion;    severe plastic deformation;    microstructure;    texture;   

DOI  :  10.3390/ma13173690

来源: DOAJ

【 摘 要 】

The rotating backward extrusion (RBE) process, as a new severe plastic deformation (SPD) process, is based on conventional backward extrusion and rotation, which meets the requirement of modern industrial development with its high performance and production efficiency. However, there is little research on the microstructure evolution and texture modification of the RBE process. Thus, in this study, the effect of different rotating revolutions, e.g., n = 5, n = 10, and n = 50, on the microstructure and texture development for the RBE process based on the AZ80 magnesium (Mg) alloy were investigated at 653 K. The results disclose that the rotating revolution is an influencing processing parameter on the deformation of the RBE process. The grain refining ability is enhanced with the increase of the rotating revolutions, and the minimum grain size of the cup bottom, shearing zone, and cup wall can reach to 16.7 μm, 15.6 μm, and 13.0 μm, respectively, under the condition of n = 50. Furthermore, with the increase in the rotating revolutions, the microstructure of the alloy becomes more uniform and the proportion of dynamic recrystallization (DRX) is also increased. The maximum DRX fractions of the sample for the cup bottom and cup wall are 95.4% and 86.8%, respectively, at n = 50. The DRX mechanism of the RBE process is determined by the continuous DRX and discontinuous DRX. In addition, the texture can be significant weakened during the RBE process, especially at the cup bottom, where the maximum pole intensity can be reduced from 17.6 at n = 10 to 6.5 at n = 50, which can be attributed to the higher proportion of new DRXed grains whose orientations are more random compared with the deformed grains.

【 授权许可】

Unknown