Investigation of Thermal-Cycling Transformation Superplasticity of As-Cast Zn-5Al-RE Alloy  

作　　者：石志强 李世春 刘宇慧 

机构地区：[1]Key Laboratory of Liquid Structure and Heredity of Materials,Shandong University [2]College of Mechanical and Electrical Engineering in the University of Petroleum

出　　处：《Journal of Rare Earths》2003年第S1期173-176,共4页稀土学报（英文版）

基　　金：ProjectsupportedbytheNationalNaturalScienceFoundationofChina (5 98710 3 1)

摘　　要：Under 20～350 ℃ thermal cycling tensile condition,the as-cast Zn-5Al-RE alloy can realize transformation superplasticity. Rare-earths added into the alloy can make the strain rate and rupture elongation decrease,while the annealing treatment has an opposite effect. The longer the annealing time,the larger the strain rate and rupture elongation will be. The effect of rare earths on the thermal-cycling transformation superplasticity of Zn-5Al-RE alloy as-cast is two-faced: on the one side,rare earths can make the eutectic structure of Zn-5Al-RE alloy fine and thus benefits superplastic deformation. On the other side,rare earths make the diffusion velocity of Zn and Al decrease and postpone the diffusion coordination process,which will hinder the viscous flow of the interphase boundaries,enhance superplastic deformation stress,and make the strain rate and elongation decrease.Under 20～350 ℃ thermal cycling tensile condition,the as-cast Zn-5Al-RE alloy can realize transformation superplasticity. Rare-earths added into the alloy can make the strain rate and rupture elongation decrease,while the annealing treatment has an opposite effect. The longer the annealing time,the larger the strain rate and rupture elongation will be. The effect of rare earths on the thermal-cycling transformation superplasticity of Zn-5Al-RE alloy as-cast is two-faced: on the one side,rare earths can make the eutectic structure of Zn-5Al-RE alloy fine and thus benefits superplastic deformation. On the other side,rare earths make the diffusion velocity of Zn and Al decrease and postpone the diffusion coordination process,which will hinder the viscous flow of the interphase boundaries,enhance superplastic deformation stress,and make the strain rate and elongation decrease.

关 键 词：Zn-Al alloy SUPERPLASTICITY TRANSFORMATION CREEP RARE-EARTHS 

分 类 号：TG135.3[一般工业技术—材料科学与工程]