半固态ZA96镁合金部分重熔过程中的组织演变  

Microstructure Evolution of Semi-Solid ZA96 Magnesium Alloy During Partial Remelting Process

作　　者：李春[1] 董晓刚[1] 袁训锋[1] 刘彦峰[1] 张美丽[1] 周春生[1] 李元东[2] 

机构地区：[1]商洛学院陕西省尾矿资源综合利用重点实验室 [2]兰州理工大学有色金属先进加工与再利用省部共建国家重点实验室

出　　处：《特种铸造及有色合金》2015年第3期268-271,共4页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(21273171);陕西省教育厅专项科研计划资助项目(14JK1223);商洛学院科研资助项目(13SKY008)

摘　　要：对自孕育法制备ZA96镁合金半固态坯料进行了部分重熔,研究了等温温度和保温时间对微观组织演变的影响。结果表明,随着等温温度增加和保温时间延长,半固态组织中固相率降低,其晶粒尺寸和圆整度呈先减小后增大的变化趋势。在530℃保温20min可获得理想的半固态组织,其平均晶粒尺寸、圆整度和固相率分别为75.69μm、1.45和58%。保温10min左右,其晶粒的粗化、枝晶臂合并及分离基本结束,其后晶粒发生球化、吞并和长大,其长大规律符合Ostwald熟化理论。The semi-solid billets of ZA96 magnesium alloy prepared by self-inoculation method were remelted partially,and effects of microstructure on remelting temperature and holdingl time were investigated.The result shows that with increasing in partial temperature and holding time,solid phase fraction is decreased,and the grain size and roundness are decreased firstly,and then increased.With partial temperature of 530 ℃for 20 min,the grain size,roundness and solid fraction reach 75.69μm、1.45and58%,respectively.Grain coarsening,merge of dendrite arm and grain separation are nearly completely with holding for 10 min.After 10 min,the microstructure evolution follows by the Ostwald ripening mechansim.

关 键 词：ZA96镁合金 部分重熔 组织演变 自孕育法 

分 类 号：TG249.9[金属学及工艺—铸造]