铸态Mg-6Zn-xZr合金晶粒细化的机制  

Grain Refinement Mechanism of Cast Mg-6Zn-xZr Alloy

作　　者：吴志林 张诗昌[1,2] 刘升[1,2] 熊九郎 

机构地区：[1]武汉科技大学材料与冶金学院 [2]武汉科技大学省部共建耐火材料与冶金国家重点实验室

出　　处：《特种铸造及有色合金》2018年第1期89-92,共4页Special Casting & Nonferrous Alloys

基　　金：武汉科技大学国防预研基金2017

摘　　要：研究了Zr含量对Mg-6Zn-xZr合金组织细化及力学性能的影响。结果表明,随Zr含量的增加,晶粒尺寸及二次枝晶间距明显减小,硬度和强度升高。采用边-边匹配模型分析了Zr及ZnZr与α-Mg之间的匹配晶面与晶向,并计算了错配度。结果表明,Zr与α-Mg存在5组晶面与晶向匹配对,ZnZr与α-Mg也存在[11 2-0]_(Mg)/[100]_(ZnZr)‖(0002)_(Mg)/(001)_(ZnZr)匹配对,因此Zr与_(ZnZr)均可作为非自发形核基底促进合金的形核并导致晶粒细化。The effects of Zr contents on microstructure refinement and mechanical properties of as-cast Mg-6Zn-xZr alloy were investigated. The results reveal that with the increase of Zr content, grain size and the secondary dendrite spacing are decreased significantly , so the hardness and strength of the alloy are improved. The matching plane and direction between Zr and ZnZr with α-Mg system were analyzed by edge-to-edge matching model, and degree of the mismatch was calculated. The results reveal that the Zr and α-Mg have five groups of plane and direction matching pairs, and ZnZr and α-Mg also exist [11 2^-0]Mg/[100]ZnZr‖（0002）Mg/（001）ZnZr matchin ous nucleation substrate to promote nucleation an g pairs, thus Zr and ZnZr can be used as a heterogene d lead to grain refinement.

关 键 词：镁锌合金 锆 晶粒细化机制 边-边匹配模型 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG115.213[金属学及工艺—金属材料]