Precipitate Characteristics and Mechanical Performance of Cast Mg–6RE–1Zn–xCa–0.3Zr(x=0 and 0.4 wt%) Alloys

作     者：Zijian Yu Xi Xu Baotian Du Kang Shi Ke Liu Shubo Li Xiuzhu Han Tao Xiao Wenbo Du Zijian Yu;Xi Xu;Baotian Du;Kang Shi;Ke Liu;Shubo Li;Xiuzhu Han;Tao Xiao;Wenbo Du

作者机构：College of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China Beijing Institute of Spacecraft System EngineeringBeijing 100094China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2022年第35卷第4期

页      面：596-608页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the National Natural Science Foundation of China(No.51801048) the Beijing Natural Science Foundation(No.2202004) the Basic Research Fund for Newly Enrolled Teachers 

主　　题：Magnesium alloy Microstructure Mechanical properties Rare earth Heat treatment 

摘      要：In this study,the Mg–4Y–1Gd–1Nd–xCa–1Zn–0.3Zr(x=0 and 0.4 wt%)cast alloys with low rare earth concentration were prepared in different routes of heat treatments,and their microstructures and mechanical properties were *** Mg–4Y–1Gd–1Nd–1Zn–0.4Ca–0.3Zr cast alloy with ultimate tensile strength(UTS)of 264±7.8 MPa,tensile yield strength(TYS)of 153±1.2 MPa and elongation to failure(EL)of 17.2±1.2% was successfully developed by appropriate heat *** improved mechanical performance was attributed to the combined strengthening effects of fine grains,Mg24RE5,β′,β_(1),γ′and LPSO *** the heat treatment process,cooling method of T4 treatment affected the microstructure,which consequently determined the mechanical properties air cooling,rather than water cooling,gave rise to the formation of γ′phase in the alloy without Ca ***,Ca addition facilitated the formation of γ′phase,and the γ′phase precipitated in the alloy after T4 treatment either by water cooling or by air cooling,but the air cooling increased the number density of γ′phase in comparison to the water *** the γ′phase strengthened the studied alloys,the formation of γ′phase inhibited the precipitatition of β′and β_(1) phases in the following T6 treatment,and consequently reduced the strengthening effect ofβ′andβ_(1) *** results showed that the mechanical performance of the studied alloys was largely determined by the precipitation of γ′phase,which was regulated by the Ca addition and the cooling method of T4 treatment.