Effect of Al3Zr particles on hot-compression behavior and processing map for Al-Cu-Li based alloys at elevated temperatures
(1. College of Materials Science and Engineering, Chongqing University, Chongqing 400045, China;
2. Chang’an Auto Global R&D Center, Chongqing 401120, China;
3. China Xipeng Aluminum Industrial Park, Chongqing 401326, China;
4. Chongqing University-University of Cincinnati Joint Co-op Institute, Chongqing University, Chongqing 401331, China;
5. College of Aerospace Engineering, Chongqing University, Chongqing 400045, China)
2. Chang’an Auto Global R&D Center, Chongqing 401120, China;
3. China Xipeng Aluminum Industrial Park, Chongqing 401326, China;
4. Chongqing University-University of Cincinnati Joint Co-op Institute, Chongqing University, Chongqing 401331, China;
5. College of Aerospace Engineering, Chongqing University, Chongqing 400045, China)
Abstract: The influence of Al3Zr particles on the hot compression behavior and processing map (PM) of Al-Cu-Li based alloys under isothermal plane-strain compression in the temperature range of 400-500 °C and at the strain rates of 0.01-10 s-1 was investigated. The corresponding microstructure was analyzed using optical microscopy (OM), electron back-scattered diffraction (EBSD) and transmission electron microscope (TEM). The results showed that dynamic recovery (DRV) played a greater role than dynamic recrystallization (DRX) in dynamic softening. At low temperatures, the Al3Zr particles were the significant barriers to inhibit DRV and DRX grain growth. When the temperature reached 500 °C, the Al3Zr particles readily spread along grain boundaries just like a necklace due to the dissolution of Al3Zr particles and rapid diffusion of Zr through grain boundary, resulting in generating the macroscopic cracks and forming an instability domain at 490-500 °C, 0.01 s-1 in the PM.
Key words: Al-Cu-Li based alloy; Al3Zr particle; hot compression; processing map