自孕育铸造对AM60镁合金晶粒细化的影响  

Effect of Self-Inoculation Cast on Grain Refinement of AM60 Magnesium Alloy

作　　者：邢博[1] 李元东[1,2] 马颖[1,2] 曲俊峰[1] 张鹏[1] 郝远[1] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,甘肃兰州730050 [2]兰州理工大学有色金属合金及加工教育部重点实验室,甘肃兰州730050

出　　处：《铸造》2010年第4期339-343,共5页Foundry

基　　金：国家973计划资助项目(2007CB613700);甘肃省国际科技合作计划资助项目(090WCGA894)

摘　　要：利用新型自孕育铸造工艺制备AM60镁合金半固态坯料,研究了自孕育铸造对合金组织的细化效果。试验结果表明,在最佳工艺参数组合下,自孕育铸造组织晶粒细小均匀,尺寸主要分布在20～50μm,晶粒平均等效圆直径达到35μm。对自孕育铸造过程中初生相形核和长大过程分析认为,孕育剂的加入促进了非均质形核效应,导流器的激冷、剪切作用促进了激冷晶的形成和树枝晶的破碎,两过程使合金凝固时晶粒增殖,抑制长大机制促进了合金组织的细化。The semi-solid AM60 billet was prepared by the novel self-inoculation method, and the effect of self-inoculation method on microstructure of the alloy was investigated. Experiment results show that under the optimized process parameters, the grains are fine and homogeneously distributed; the grain size mainly in the range of 20-50 μm and the average size is 35 μm. Further analysis show that the heterogeneous nucleation was enhanced as the addition of inoculation; the formation of chill crystal and the fragmentation of dendrites were promoted by cooling and shearing action of the cooling channel, which resulting in the increase of grains density and a small grain size.

关 键 词：AM60镁合金 自孕育铸造 晶粒细化 晶粒度 

分 类 号：TG27[金属学及工艺—铸造]