Microstructure comparison of ZK60 alloy under
casting, twin roll casting and hot compression
casting, twin roll casting and hot compression
(1. School of Mechanical Engineering, University of Ji’nan, Ji’nan 250022, China;
2. School of Materials Science and Engineering, Shandong University, Ji’nan 250022, China;
3. Korea Institute of Materials Science, 66 Sangnam-dong, Changwon 641010, Korea)
2. School of Materials Science and Engineering, Shandong University, Ji’nan 250022, China;
3. Korea Institute of Materials Science, 66 Sangnam-dong, Changwon 641010, Korea)
Abstract: The microstructures of ZK60 alloy under conventional direct as-casting (DC), twin roll casting (TRC) and twin roll casting followed by hot compression (TRC-HC) were analyzed by optical morphology (OM), electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). The deformation condition of hot compression is 350 ℃, 0.1 s−1. The microstructural evolution under TRC-HC deformation followed by annealing at different temperatures and time was discussed. The results show that TRC provides more modified microstructure compared with DC. Twins are found in TRC processing; dynamic recrystallization (DRX), shear bands and twins are found in TRC-HC. A short annealing time has little effect on hardness, while during a long time annealing, it is found that low annealing temperatures increase the micro-hardness and high temperature decreases it.
Key words: microstructural evolution; anneal; dynamic recrystallization; static recrystallization; twin-roll casting; hot compression; magnesium alloy ZK60