Y对Mg-3Nd-0.3Zr合金动态应变时效的影响

摘要

针对稀土元素Y对Mg-3Nd-0.3Zr 合金动态应变时效的影响.文中在恒定应变速率4.17×10-5s-1下,室温和200 ℃条件下进行压缩实验.研究结果表明:稀土元素 Y 的添加引起锯齿形态和力学性能发生变化.Mg-3Nd-0.3Zr和Mg-5Y-3Nd-0.3Zr在 200 ℃时出现动态应变时效(DSA)现象,锯齿类型分别为 B型和 C 型,临界应变量分别为 4.98%和 2.20%,应力跌幅的概率统计分布分别为单峰型和双峰型;DSA 对 Mg-5Y-3Nd-0.3Zr 合金 200 ℃的屈服强度提高不明显.锯齿类型的改变与Y原子的添加使溶质原子扩散困难和可动位错运动受阻有关.%The influence of the rare earth element yttrium on the dynamic strain aging (DSA)of Mg-3Nd-0.3Zr alloy is investigated.A series of compressive tests were conducted at room temperature and 200 ℃ at a constant rate 4.17×10-5s-1.The results show that the addition of Y causes changes in the type of serration and mechanical properties.The DSA phenomenon occurs at 200 ℃ in Mg-3Nd-0.3Zr and Mg-5Y-3Nd-0.3Zr,whose serrated types are type B and type C.Their critical strains are 4.98% and 2.20%,r,and their probability statistics distributions of stress drop magnitudes are unimodal type and bimodal type,respectively.DSA does no obvious contribution to the enhancement of the strength in Mg-5Y-3Nd-0.3Zr at 200 ℃.Transition of serrated types is related to the difficult diffusion of solute atoms and the impediment of mobile dislocations which are caused by the addition of Y.