Effect of pouring and mold temperatures on fluidity and hot tearing behavior of cast Al-Li-Cu-Mg-Sc-Zr-Ti alloy
(1. National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. Jiangxi Ganfeng Lithium Co., Ltd., Xinyu 338004, China)
2. Jiangxi Ganfeng Lithium Co., Ltd., Xinyu 338004, China)
Abstract: The influence of pouring temperature and mold temperature on the fluidity and hot tearing behavior of Al-2Li-2Cu-0.5Mg-0.15Sc-0.1Zr-0.1Ti alloys was investigated by experimental investigation and simulation assessment. The results showed that the length of the spiral fluidity sample increases from 302 to 756 mm as the pouring temperature increases from 680 to 740 °C, and from 293 to 736 mm as the mold temperature increases from 200 to 400 °C. The hot tearing susceptibility (HTS) firstly decreases and then increases with increasing pouring and mold temperatures, which is mainly caused by the oxide inclusion originating from the high activity of Li at excessive pouring temperature. Excessive pouring and mold temperatures easily produce oxide inclusions and holes, leading to a reduction in fluidity and an increase in HTS of the alloy. Combining the experimental and simulation results, the optimized pouring and mold temperatures are ~720 °C and ~300 °C for the cast Al-Li alloy, respectively.
Key words: pouring temperature; mold temperature; fluidity; hot tearing behavior; cast Al-Li alloy; numerical simulation