空位对Cu/Sn无铅焊点界面元素扩散的影响  

Effect of vacancy on the elements diffusion in Cu/Sn lead-free solder joints

作　　者：李扬[1] 李晓延[1] 姚鹏[1] LI Yang;LI Xiaoyan;YAO Peng(College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China)

机构地区：[1]北京工业大学材料科学与工程学院,北京100124

出　　处：《焊接学报》2018年第12期25-30,130,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(5157011);北京市自然科学基金资助项目(2162002)

摘　　要：界面柯肯达尔空洞形成的过程伴随着空位的形成与扩散,对空位行为的研究有利于深入理解界面扩散和空洞形成过程.运用分子动力学方法模拟Cu/Cu_3Sn界面上空位对扩散的影响,计算空位形成能、扩散势垒及空位扩散激活能.结果表明,相同条件下含空位的模型发生扩散的几率要高于不含空位的模型.另外,计算表明铜晶体的空位形成能大于Cu_3Sn晶体中铜空位的形成能;Cu_3Sn晶格中不同晶位的Cu空位(Cu1空位和Cu2空位)的形成能比较接近,但均小于锡的空位形成能.此外,对Cu/Cu_3Sn界面的空位扩散势垒及空位扩散激活能的计算结果表明,Sn原子的空位扩散激活能高于Cu原子.The formation process of interface Kirkendall voids is accompanied by the formation and diffusion of vacancies,so the behavior can not be ignored during interfacial diffusion and void formation process.In this study,the diffusion process of Cu-Sn interface and the effect of vacancies on diffusion in Cu/Cu3interface were investigated using molecular dynamics simulation.Moreover,the diffusion behaviors of atoms were analyzed,while the vacancy formation energy,diffusion energy barrier and vacancy diffusion activation energy were obtained.By comparison,it was found that the models containing vacancies more easily formed diffusion than the models without vacancies.In addition,the formation energy of Cu vacancy in the Cu crystal was greater than that in Cu3Sn crystal.The formation energies of Cu1vacancy and Cu2vacancy were close to each other in Cu3Sn crystal,and they were both smaller than the formation energy of Sn vacancy.Furthermore,the vacancy diffusion barrier and vacancy diffusion activation energy of the Cu/Cu3Sn interface were calculated.The results showed that the vacancy diffusion activation energy of Sn was higher than that of Cu.

关 键 词：Cu/Cu3Sn 分子动力学模拟 空位 扩散势垒 扩散激活能 

分 类 号：TG406[金属学及工艺—焊接]