母合金成分对受控扩散凝固铸造ZA27合金组织的影响  

Effects of Precursor Alloy Composition on Microstructure of ZA27 Alloy Prepared by Controlled Diffusion Solidification

作　　者：蔡其勇[1] 李元东[1,2] 李明[1] 杨雄[1] 马颖[1,2] 

机构地区：[1]兰州理工大学省部共建有色金属先进加与再利用国家重点实验室 [2]兰州理工大学有色金属合金及加工教育部重点实验室

出　　处：《特种铸造及有色合金》2017年第1期57-61,共5页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51464031)

摘　　要：采用受控扩散凝固技术铸造ZA27合金,研究了母合金成分对受控扩散凝固铸造ZA27合金组织的影响。结果表明,受控扩散凝固能够细化ZA27合金的组织,改善组织形貌。随着母合金2(Al-Zn-Cu-Mg合金)中Zn含量的增加,母合金1(纯Zn)对母合金2的激冷与对流搅拌作用减弱,受控扩散凝固技术对ZA27合金组织的影响减弱。当母合金2中Zn含量为0时,晶粒尺寸最小,仅为95.9μm,呈不规则的颗粒状;母合金2中Zn含量为10%时,晶粒尺寸为103.8μm,开始出现等轴晶;母合金2中Zn含量为30%时,晶粒尺寸达到137.3μm,略小于ZA27合金传统铸造的145.6μm,出现树枝晶;当母合金2中Zn含量达到40%时,晶粒尺寸达到145.4μm,受控扩散凝固技术对ZA27合金组织的影响基本消失。ZA27 alloy was prepared by controlled diffusion solidification,and effects of precursor alloy composition on microstructure of the ZA27 alloy prepared were investigated.The results show that the grain size of ZA27 alloy can be refined,and the microstructure morphology is improved by controlled diffusion solidification.With increasing in Zn content in precursor alloy 2（Al-Zn-Cu-Mg alloy）,the chilling and forced convection of precursor alloy 1（Pure Zn）on precursor alloy 2are weakened,so the effect of controlled diffusion solidification on ZA27 alloy microstructure was decreased.When the content of Zn in precursor alloy 2is 0,the grain size with irregular particle structure is 95.9μm.When the content of Zn in precursor alloy 2reaches 10%,the grain size is increased to 103.8μm,and a part of equiaxed grain can be observed.Whereas it reaches 30%,the grain size is increased to 137.3μm,slightly less than 145.6μm of ones produced by traditional casting,and the dendritic morphology can be observed.After the content of Zn in precursor alloy 2is increased to 40%,the grain size of ZA27 alloy prepared reaches 145.4μm,which reveals that the effect of controlled diffusion solidification on microstructure of ZA27 alloy almost disappear.

关 键 词：ZA27合金 受控扩散凝固 母合金 

分 类 号：TG292[金属学及工艺—铸造]