Cu-8%Ag合金的超重力凝固:微观组织  

The effect of hypergravity on the solidification structure and properties of Cu-8%Ag alloy

作　　者：闫昊 韦华[1,2] 林伟岸 张泽[1] 陈云敏[2] YAN Hao;WEI Hua;LIN Wei-an;ZHANG Ze;CHEN Yun-min(School of Materials Science and Engineering,Zhejiang University,Hangzhou Zhejiang 310027;Center for Hypergravity Experimental and Interdisciplinary Research,Zhejiang University,Hangzhou Zhejiang 310058,China)

机构地区：[1]浙江大学材料科学与工程学院,浙江杭州310027 [2]浙江大学超重力研究中心,浙江杭州310058

出　　处：《电子显微学报》2022年第1期1-7,共7页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金基础科学中心项目(No.51988101).

摘　　要：在常重力场和N g超重力场下制备了Cu-8%Ag(质量分数)合金试样,研究了超重力对Cu-8%Ag合金凝固组织的影响。结果表明,超重力引起的熔体对流对试样底部的冲刷作用强于试样顶部,造成底部柱状枝晶的生长弱于试样顶部,超重力试样得到了细小均匀的等轴晶区,Ag棒状析出相的直径由常重力的56.1 nm细化到超重力下的39.2 nm,超重力没有产生明显的宏观偏析,但会影响Ag在Cu基体和离异共晶组织中的分布。Cu-8%Ag(mass fraction) alloy samples were prepared under the normal gravity and hypergravity condition. The effect of hypergravity on the microstructures of Cu-8%Ag alloy was investigated. The obtained results show that the melt convection caused by hypergravity on the bottom of the crucible is much stronger than that on the top of the crucible, resulting in an abruptly suppression of the growth of columnar dendrites at the bottom of the sample compared with that on the top of the sample. It is why a large fine and uniform equiaxed crystal region is formed in the middle of the sample prepared under the hypergravity condition. The average diameter of the rod-like Ag precipitates decreases from about 56.1 nm under normal gravity condition to about 39.2 nm under hypergravity condition. It is observed that hypergravity field does not produce an obvious macro-segregation whereas it can have an important impact on the distribution of Ag in the Cu matrix and the divorced eutectic in the prepared samples.

关 键 词：超重力 CU-AG合金 凝固组织 晶粒细化 

分 类 号：TG146.11[一般工业技术—材料科学与工程] TG132.21[金属学及工艺—金属材料]