异步轧制AZ31镁合金板材组织
来源期刊:中南大学学报(自然科学版)2008年第6期
论文作者:刘先兰 张文玉 刘楚明 李慧中 曾苏民
文章页码:1244 - 1250
关键词:异步轧制;AZ31镁合金;微观组织
Key words:differential speed rolling; AZ31 magnesium alloy sheet; microstructure
摘 要:对不同总变形量、道次压下量、轧制温度以及轧制路径等工艺条件下所制备的AZ31镁合金板材的组织进行研究。研究结果表明:异步轧制有利于板材的晶粒细化,其晶粒粒度约为8.9 μm,明显小于常规轧制板材的13.2 μm;当总变形量由40%增大到80%时,晶粒粒度从40 μm左右减小到30 μm左右,出现了较多的孪晶;当道次压下量由5%增加到20%时,晶粒粒度从40 μm左右减小到10~20 μm,孪晶数量也随之减少;当温度由350 ℃升高到400 ℃时,晶粒粒度由20 μm左右下降到10 μm,且大部分晶粒为等轴晶;轧制路径的改变,使板材中的显微组织和孪晶数量产生改变,C路径中的晶粒细小,粒度约为10 μm,D路径中的孪晶数量最少。
Abstract: The microstructures of AZ31 magnesium alloy sheets produced by differential speed rolling were investigated from total thickness reduction ratio, pass thickness reduction ratio, rolling temperature and rolling routes. The results show that the grain size of AZ31 magnesium alloy sheet is refined from 13.2 μm processed by normal rolling to 8.9 μm processed by differential speed rolling; during the differential speed rolling, the grain size of AZ31 magnesium alloy sheet is refined from 40 μm to about 30 μm and there are lots of twins with the increase of total thickness reduction ratio from 40% to 80%; the percentage of twins is reduced with the increase of pass thickness reduction ratio from 5% to 20% and the grain size is refined from 40 μm to 10-20 μm; with the increase of temperature from 350 ℃ to 400 ℃, grains are fined from 20 μm to 10 μm, and there are mostly equiaxed grains; the microstructure and the number of twins are changed with the change of the routes of rolling, the grain size is about 10 μm in the route C, and in the route D, there are least twins.
基金信息:湖南省自然科学基金资助项目
湖南省科技计划项目