Effect of Ca addition on the microstructure and mechanical properties of heat-treated Mg-6.0Zn-1.2Y-0.7Zr alloy  

作　　者：Young Gil Jung Wonseok Yang Yong Joo Kim Shae.K.Kim Young Ok Yoon Hyunkyu Lim Do Hyang Kim 

机构地区：[1]Advanced Materials and Process R&D Department,Korea Institute of Industrial Technology,156,Gaetbeol-ro,Incheon 21999,Republic of Korea [2]Department of Metallurgical Engineering,Yonsei University,50,Yonsei-ro,Seoul,Seodaemun-gu 03722,Republic of Korea

出　　处：《Journal of Magnesium and Alloys》2021年第5期1636-1648,共13页镁合金学报（英文）

基　　金：the support of the Korea Institute of Industrial Technology as"Enterprise demand-based production technology commercialization project(KITECH JG-20–0003)"。

摘　　要：In this study,the effects of Ca addition on the microstructure,thermal properties,and mechanical properties of a Mg-6.0Zn-1.2Y-0.7Zr(ZWK611)alloy at room temperature and 150℃ were investigated.With an increase in the Ca content,the ignition resistance of the ZWK611 alloy improved and the grains became finer.The as-cast ZWK611 alloy consisted mainly of the dendriticα-Mg matrix and I-phase(Mg_(3)Zn_(6)Y)at the grain boundaries.On the other hand,theτ-(Ca_(2)Mg_(6)Zn_(3))and I-phases were formed in the Ca-added ZWK611 alloy.The fraction of theτ-phase increased with an increase in the Ca content.After the solid-solution treatment,these phases remained partially at the grain boundaries of the Ca-added ZWK611 alloys and an additional W-phase(Mg_(3)Zn_(3)Y)was observed.The phases remaining at the grain boundaries restricted the grain growth through the grain boundary pinning effect.The aging treatment resulted in the formation of MgZn'precipitates in theα-Mg matrix of the alloys.These precipitates were more uniformly distributed in the Ca-added alloys than in the alloys without Ca.Thus,the heat treatment-induced precipitation improved the tensile and creep properties of the T6-treated alloys.The T6-treated ZWK611+0.7Ca alloy exhibited the best mechanical properties at room temperature and 150℃ among all the tested alloys.

关 键 词：Mg-Zn-Y alloys Heat-treatment PRECIPITATE Mechanical properties Thermal analysis 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG156[金属学及工艺—金属材料]