纳米压痕法研究80Au/20Sn焊料蠕变应力指数  

Investigation of creep stress exponent of 80Au/20Sn solder by nanoindentation

作　　者：张国尚[1] 荆洪阳[1] 徐连勇[1] 魏军 韩永典[1] 

机构地区：[1]天津大学材料科学与工程学院,天津300072 [2]新加坡制造技术研究院,新加坡638075

出　　处：《焊接学报》2009年第8期73-76,共4页Transactions of The China Welding Institution

基　　金：教育部新世纪优秀人才基金资助项目(NCET-06-0235);国家自然科学基金资助项目(50575160);教育部高等学校博士点基金资助项目(20050056035)

摘　　要：室温下通过恒加载速率/载荷纳米压痕法对铸态80Au/20Sn焊料进行了测试,得到了压痕试样的载荷—位移曲线.试验表明,加载速率对载荷一位移曲线影响显著,较低的加载速率产生了较大的位移变化;加载阶段,较低的加载速率导致了较大的压痕深度;载荷保持阶段,压痕深度的变化表明在该阶段发生了蠕变,较高的加载速率导致了较大的蠕变应变率.结果表明,基于压痕做功概念得到的蠕变应力指数与传统单轴拉伸或压缩蠕变测试得到的数值具有较好的一致性,该测试和分析方法可行.Eutectic 80Au/20Sn solder alloy is widely used in high power electronics and optoelectronics packaging in which the creep property of the solder joint is essential to meet the global demand for longer operating lifetime.The creep stress exponent describing the creep behaviour of the material is often obtained by conventional tensile or compressive creep tests.However,the testing methods are often tedious.In this study,the creep stress exponent value determined by nanoindentatoin tests based on the concept of 'work of indentation' agrees with that determined by uniaxial tensile and compressive creep tests.It indicates that such nanoindentaion tests and analysis provide a cheaper and more convenient method to evaluate the creep properties of solder alloys.To some extent,the results can be explained by the similarities and differences among the testing methods.

关 键 词：蠕变应力指数 单轴拉伸蠕变测试 纳米压痕 压痕功 

分 类 号：TG115.56[金属学及工艺—物理冶金]