加热工艺对冷轧6061合金半固态显微组织的影响

Effect of Heating Process on Semi-solid Microstructure of Cold Rolled 6061 Aluminum Alloy

基于SIMA法,采用冷轧+半固态热处理工艺制备出6061铝合金半固态坯料。研究了半固态加热温度和保温时间对6061铝合金半固态坯料显微组织的影响。结果表明:随半固态加热温度的升高,α-Al固相颗粒的球形率增大,液相率升高;保温时间在0~15 min内,随保温时间的延长,α-Al固相颗粒越圆整、分布越均匀,液相率越高;当保温时间超过15 min后,α-Al固相颗粒尺寸逐渐增大,颗粒有簇聚的趋势,而液相率变化不明显;优化的加热工艺参数为630℃保温15 min,可获得6061铝合金半固态坯料理想的显微组织。

Based on SIMA process, the semi-solid billets of 6061 aluminum alloy were prepared by cold rolling following semi-solid isothermal treatment. The effects of semi.solid heating temperature and holding time on the microstructure of the semi-solid billets of 6061 aluminum alloy were investigated. The results show that with the increase of semi-solid heating .temperature, the spherical rate of a-Al solid particle increases, and the liquid fraction increases; within the holding time of 0-1,5 vain, with the increase of holding time,a-Al solid particles are rounder and more uniformly distributed, the liquid fraction is higher; when the holding time is above 15 min, the size of ct-A1 solid particle increases, and the solid particles haveothe trend of cluster, the liquid fraction increases inconspicuously, The optimization parameter of heating process is 630.℃×15min, and then the 6061 aluminum alloy semi-solid billet with ideal microstructure can be obtained.