Shear strength of Sn-3.5Ag solder and Sn-3.5Ag/Cu joint
The multiscale microstructures and shear properties of Sn-3.5Ag at different cooling rates and Sn-3.5Ag/Cu joint have been studied.Results show that when the cooling rate decreased from 3.5K/s to 1.0K/s,short-needlelike bulk Ag3Sn in-termetallic compounds (IMCs) formed and dispersed homogeneously in matrix.Simultaneously,eutectic region was refined.Linear increasing relationship on log-log plot was obtained between shear strength and shear strain rate for all samples.The shear strength of Sn-3.5Ag solder at fast cooling rate was higher than that at a slow cooling rate,but both were smaller than that of joint.The strain sensitivity exponent m for bulk solders at 1.0K/s,3.5K/s and joint was 0.094,0.076 and 0.082,respectively.Fractography analysis indicated all the solder samples,and Sn-3.5Ag/Cu joint at low strain rates (0.lrad/s and lrad/s),exhibited ductile fracture no matter what cooling rate.At high strain rate (10rad/s),broken Cu6Sn5 were found in the fractography of Sn-3.5Ag/Cu joint.However,the main part of the fractography was still composed of dimples,which indicated mixed fracture happened.
Sn-3.5Ag Sn-3.5Ag/Cu Strain sensitivity Shear Fracture
Zhongbing Luo Lai Wang Yanjun Gao Jie Zhao
School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,China
国际会议
成都
英文
511-515
2009-10-16（万方平台首次上网日期，不代表论文的发表时间）