钙对Mg-6Al变形镁合金显微组织和拉伸性能的影响

Effect of Calcium on Microstructure and Tensile Properties of Mg-6Al Wrought Magnesium Alloy

研究了钙含量对Mg-6Al变形镁合金显微组织和拉伸性能的影响。结果表明:随着钙含量的增加,Mg-6Al合金中的-βMg17Al12相逐渐变少、变细,铸态晶粒明显细化;大部分钙和铝结合生成高熔点Al2Ca相,能够阻碍晶粒的长大,使晶粒细化;钙的添加量少于1%时,随着钙含量的增加,合金的室温抗拉强度和伸长率均提高,钙的添加量大于1%时,合金的拉伸性能下降;钙含量为1%时,合金室温抗拉强度比不加钙时的提高了33.3%,伸长率达到2.65%,提高了1倍多。

Effects of Ca content on microstructure and mechanical properties of Mg-6Al wrought magnesium alloy were investigated. It was found that with the increase of Ca content, β-Mg17 Al12 phase of the alloy gradually changed little and thinner and the cast grain size was also refined obviously. Most Ca in the alloy reacted with Al to form compounds of Al2Ca with high melting point which could hider the grain growth and refined the grain. When the Ca content was less than 1wt%, the strength and elongation raised with the increase of Ca content. However, when it exceeded 1wt%, the mechanical properties decreased. When the Ca content was 1wt%, the alloy had the best properties with tensile strength being increased by 33.3% and elongation of 2. 65% being increased by more than one time.