Ti_(2)ZrNbV高熵合金的相稳定性和时效强化

Phase Stability and Aging Strengthening of Ti_(2)ZrNbV High Entropy Alloy

采用真空电弧熔炼法制备了具有体心立方结构的Ti_(2)ZrNbV(at%)高熵合金。研究了固溶体相的稳定性,以及金属间化合物V_(2)Zr析出对拉伸性能的改善。结果表明:合金在900℃以上是稳定单一均质固溶体相,低于此温度时,Laves相V_(2)Zr容易在基体中析出。单一固溶相的不稳定性可用于强化Ti_(2)ZrNbV高熵合金。经过固溶和时效处理后,合金的拉伸屈服强度可达1145 MPa,塑性伸长率为8.3%。

A bcc-structured Ti_(2)ZrNbV(at%)high entropy alloy was prepared by vacuum arc melting.The stability of the solid solution phase was studied,and the improvement of tensile property via V_(2)Zr phase precipitation was investigated.The results show that the homogenous solid solution phase is stable above 900℃,and Laves phase V_(2)Zr easily precipitates below this temperature.The instability of the solid solution phase can be used for enhancing the Ti_(2)ZrNbV alloy.After solid solution and aging treatment,the tensile yield strength of the alloy can reach 1145 MPa with a promising elongation of 8.3%.