Cu/SAC305/Cu微焊点的剪切蠕变试验及数值模拟  

Experiment and Numerical Simulation of Shear Creep of Cu/SAC305/Cu Microscale Solder Joints

作　　者：尹立孟[1] 苏子龙 左存果 张中文 姚宗湘[1] 王刚[1] 王善林[2] 陈玉华[2] YIN Limeng;SU Zilong;ZUO Cunguo;ZHANG Zhongwen;YAO Zongxiang;WANG Gang;WANG Shanlin;CHEN Yuhua(School of Metallurgy and Materials Engineering,Chongqing University of Science&Technology,Chongqing 401331;School of Aviation Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330063)

机构地区：[1]重庆科技学院冶金与材料工程学院,重庆401331 [2]南昌航空大学航空制造工程学院,南昌330063

出　　处：《机械工程学报》2022年第2期300-306,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52175288);重庆市自然科学基金(cstc2019jcyjmsxmX0175,cstc2020jcyj-msxmX0552,cstc2020jcyj-msxmX0564)资助项目。

摘　　要：采用基于动态力学分析仪(DMA Q800,TA-Instruments)的精密蠕变试验,针对直径400μm、高250μm的Cu/Sn-3.0Ag-0.5Cu/Cu无铅微尺度焊点,研究了其在10 MPa恒定应力和不同温度(100℃、110℃、120℃)以及100℃恒定温度和不同应力(8 MPa、10 MPa、12 MPa)条件下的剪切蠕变。同时,借助有限元分析软件ABAQUS进行了焊点的剪切蠕变数值模拟。试验结果表明,在10 MPa下剪切蠕变激活能Q为114.5 kJ/mol,100℃下微焊点剪切蠕变应力指数n为6.12。模拟结果显示,在10 MPa下剪切蠕变激活能Q为105.49 kJ/mol,100℃下微焊点剪切蠕变应力指数n为6.67。结合试验和模拟所得的蠕变激活能、应力指数认为,焊点剪切蠕变机制以晶格扩散机制为主。焊点断口形貌显示,剪切蠕变断裂路径穿过钎料基体并靠近SAC305钎料/IMC界面区域,表现为典型韧性断裂。Based on the dynamic mechanical analyzer(DMA Q800,TA-Instruments),the shear creep of Cu/Sn-3.0Ag-0.5Cu/Cu lead-free microscale solder joints with a diameter of 400μm and a height of 250μm was studied under constant stress(10 MPa)and different temperatures(100℃,110℃,120℃),and a constant temperature(100℃)under different stresses(8 MPa,10 MPa,12 MPa).Then,the finite element analysis software ABAQUS was adopted to simulate the shear creep under the same conditions as the experiment.The experiment results show that the activation energy(Q)of SAC305 solder joint is 114.5 kJ/mol under the shear stress of 10 MPa,and the shear creep stress index n is 6.12 at 100℃.The simulation results show that the activation energy is 105.49 kJ/mol under 10 MPa,and the shear creep stress index is 6.67 at 100℃.According to the creep activation energy and creep stress index,the shear creep mechanism is mainly the lattice diffusion mechanism.In addition,the shear creep fracture pass through the solder matrix and close to the SAC305 solder/IMC interface region,and the fracture is typical ductile fracture.

关 键 词：电子封装 微尺度焊点 蠕变 数值模拟 剪切应力 

分 类 号：TG113[金属学及工艺—物理冶金]