α-CoSn_(3) IMC弹性模量各向异性的第一性原理  

First-principles study on anisotropy of elastic modulus of α-CoSn_(3) IMC

作　　者：冉藤 樊涛 杜飞 翟翔 杨栋华[1] 黄福祥[2] RAN Teng;FAN Tao;DU Fei;ZHAI Xiang;YANG Donghua;HUANG Fuxiang(Special Welding Materials and Technology Chongqing University Engineering Research Center,Chongqing University of Technology,Chongqing,400054,China;Chongqing University of Technology,Chongqing,400054,China)

机构地区：[1]重庆理工大学,特种焊接材料与技术重庆市高校工程研究中心,重庆400054 [2]重庆理工大学,重庆400054

出　　处：《焊接学报》2021年第6期71-76,I0005,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(61804018);重庆市教委科学技术研究计划项目(KJQN202001124);重庆市基础研究与前沿技术研究计划(cstc2016jcyjA0226).

摘　　要：焊点微型化的同时,界面IMC在整个焊点中所占比例显著增大,微焊点在服役过程中对界面IMC的取向变得更加敏感.文中基于密度泛函理论计算了α-CoSn_(3)的晶格常数和弹性模量各向异性,并比较了常见IMC的各向异性指数.结果表明,[100]方向的抗线性压缩能力小于其它两个主晶轴;(100)剪切面抵抗剪切变形的能力大于其它两个主晶面.根据差分电子密度图分析了成键轨道的具体贡献.α-CoSn_(3)三维弹性模量随晶体取向变化的三维图及投影图直观的展现它们各向异性的性质.计算了α-CoSn_(3)各向异性指数,并与常见IMC比较了各向异性程度,得到α-CoSn_(3)各向异性程度居中的结论.While the solder joints are miniaturized,the proportion of interface IMC in the entire solder joints has increased significantly,and the micro solder joints become more sensitive to the orientation of the interface IMC during the service process.Therefore,this work is based on density functional theory to calculate the lattice constant and elastic modulus anisotropy ofα-CoSn_(3),and compares the anisotropy indices of common IMCs.The results show that the resistance to linear compression in the[100]direction is less than that of the other two main crystal axes;the(100)shear plane is more resistant to shear deformation than the other two main crystal planes.According to the differential electron density map,the specific contribution of the bonding orbital is analyzed.The three-dimensional graphs and projection graphs of the threedimensional elastic modulus ofα-CoSn_(3) varying with crystal orientation intuitively show their anisotropic properties.The anisotropy index ofα-CoSn_(3) was calculated,and compared with other common IMCs in brazing,the anisotropy degree ofα-CoSn_(3) was found to be in the middle.

关 键 词：IMC 第一性原理 各向异性 弹性 

分 类 号：TG425[金属学及工艺—焊接]