铸态Mg-4Zn-xGa合金的组织与性能研究  

Microstructure and Properties of As-cast Mg-4Zn-xGa Alloys

作　　者：朱伟俊 陈吉华[1,2] 严红革 夏伟军[1,2] 苏斌 黄文森[1] 巩晓乐 ZHUWeijun;CHEN Jihua;YAN Hongge;XIAWeijun;SU Bin;HUANGWensen;GONG Xiaole(Schoolof Materials Science and Engineering,Hunan University,Changsha 410082,China;Hunan Provincial Key Laboratory of Spray Deposition Technology&Application,Changsha 410082,China)

机构地区：[1]湖南大学材料科学与工程学院,长沙410082 [2]湖南省喷射沉积技术及应用重点实验室,长沙410082

出　　处：《腐蚀科学与防护技术》2019年第6期590-596,共7页Corrosion Science and Protection Technology

基　　金：国家自然科学基金(51571089)~~

摘　　要：采用金相分析、扫描电镜分析、拉伸测试和耐腐蚀性能测试等手段,研究了Ga含量(质量分数为1%,2%和5%)对铸态Mg-4Zn基合金显微组织、力学性能和耐生体腐蚀性能的影响。结果表明:Ga的加入可以明显细化铸态合金的晶粒,增加合金中第二相的体积分数,显著提高合金的强度和塑性。其中Mg-4Zn-2Ga合金的综合性能最佳,其抗拉强度、屈服强度和断后伸长率分别为233 MPa、90 MPa和24%,比基体合金分别提高了13.6%、76.5%和33.3%。然而,Ga的加入降低了Mg-4Zn合金的耐生体腐蚀性能,但是Mg-4Zn-5Ga合金的耐蚀性优于Mg-4Zn-2Ga和Mg-4Zn-1Ga合金。铸态Mg-4Zn-5Ga合金在37℃Hank's溶液中浸泡7 d的平均腐蚀速率为2.3 mg/(cm^2·d),腐蚀电流密度为29.5μA/cm^2。Effect of Ga addition(1%,2%and 5%,mass fraction)on microstructure,mechanical property and bio-corrosion resistance of the as-cast Mg-4Zn based alloys were investigated by OM,SEM,tensile testing and immersion test in Hank's solution.The Ga addition has a great effect on the grain refinement of the as-cast Mg-4Zn alloys,causing the increase of the amount of second phase particles and improving the ultimate tensile strength,the yield strength and the elongation to rupture.The as-cast Mg-4Zn-2Ga alloy exhibits the best comprehensive mechanical properties,with the ultimate tensile strength,yield strength and elongation to rupture of 233 MPa,90 MPa and 24%,respectively,which are approximately 13.6%,76.5%and 33.3%higher than the counterpart Mg-4Zn alloy.However,the Ga addition deteriorates the corrosion resistance of Mg-4Zn based alloys,even so,the Mg-4Zn-5Ga alloy exhibits better corrosion resistance than the Mg-4Zn-2Ga and the Mg-4Zn-1Ga alloys.The average corrosion rate and corrosion current density of the as-cast Mg-4Zn-5Ga alloy immersed in Hank's for 7 d are 2.3 mg/(cm^2·d)and 29.5μA/cm^2 respectively.

关 键 词：Mg-Zn-Ga合金 显微组织 力学性能 耐生体腐蚀性能 

分 类 号：TG172[金属学及工艺—金属表面处理]