Liu Huiling, Meng Yingze, Yu Huisheng, Xu Wenlong, Zhang Siyang, Jia Leichen, Wu Guoqin
Mechanics Institute, Jinzhong University, Jinzhong 030619, China.
College of Mechanical and Electrical Engineering, North University of China, Taiyuan 030051, China.
Materials (Basel). 2020 Jul 24;13(15):3290. doi: 10.3390/ma13153290.
The Mg-Gd-Y-Zn-Zr alloy containing a long period stacking ordered (LPSO) phase was subjected to multi-pass deformation by means of a multi-directional forging process, and the microstructure evolution and the influence of the LPSO phase on its dynamic recrystallization (DRX) were studied. The results showed that multi-directional forging can effectively refine the grain with the DRX fraction increased, and DRXed grains lead to the decrease of the texture intensity, which can significantly improve the mechanical properties of the alloy. The different morphologies of the LPSO phase have different degrees of promotion relative to DRX behavior. The lamellar LPSO phase with kinks promoted dislocation plugging, where there could be a potential nucleation site for DRX grains. The fragmented lamellar LPSO phase promoted the DRX process through the particle-stimulated nucleation mechanism, and the block-shaped phase was more prone to stress concentration, which promoted DRX. These effects resulted in continuous grain refinement and a more uniform microstructure.
对含有长周期有序堆积（LPSO）相的Mg-Gd-Y-Zn-Zr合金采用多向锻造工艺进行多道次变形，研究了其微观组织演变以及LPSO相对其动态再结晶（DRX）的影响。结果表明，多向锻造可有效细化晶粒，使DRX分数增加，且DRX晶粒导致织构强度降低，这可显著提高合金的力学性能。LPSO相的不同形态对DRX行为有不同程度的促进作用。具有扭折的层状LPSO相促进位错塞积，此处可能是DRX晶粒的潜在形核位置。破碎的层状LPSO相通过粒子激发形核机制促进DRX过程，而块状相更容易产生应力集中，从而促进DRX。这些作用导致晶粒持续细化且微观组织更加均匀。
