纳米压入法研究无铅焊料应变率敏感性  

Nanoindentation characterization of strain rate sensitivity of lead-free solders

作　　者：贾春楠 肖革胜[1] 袁国政[1] 李志刚[1] 树学峰[1] 

机构地区：[1]太原理工大学应用力学与生物医学工程研究所,太原030024

出　　处：《功能材料》2015年第1期1046-1050,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(11172195);山西省研究生优秀创新资助项目(20133038)

摘　　要：采用纳米压入法对Sn-3.0Ag-0.5Cu、Sn-0.7Cu及Sn-3.5Ag无铅焊料的室温应变率敏感性进行研究。相同压深下,压入载荷随着加载应变率的提高而增大;3种焊料的接触刚度均随压深近似线性增加,不同应变率下弹性模量基本不变;硬度随着应变率的增加而增大,表明了无铅焊料的塑性应变率强化性。保载阶段蠕变位移随加载段应变率的增加而增大,蠕变应变率先急剧下降然后趋于稳定。通过系统研究应变率对3种常用无铅焊料力学性能的影响,为评价无铅焊点的服役可靠性提供参考。Nanoindentation tests were conducted on lead-free solders of Sn-3.0Ag-0.5Cu,Sn-0.7Cu and Sn-3.5Ag to investigate the strain rate sensitivity at room temperature.For the lead-free solders,indentation load under the same indentation depth increases with increasing loading strain rate.The contact stiffness during loading in-creases with indentation depth approximatively linearly,and the elastic modulus of the lead-free solders under different strain rates basically remains unchanged.The hardness increases as strain rate increases,indicating the strain rate hardening effect of viscous solders.During the holding stage,creep displacement increases with in-creasing strain rate during loading,while the creep strain rate firstly declines sharply and then stabilizes.Effects of stain rate on the mechanical properties of lead-free solders was systematically studied,providing valuable in-formation for the reliability evaluation of lead-free solder j oints in the service process.

关 键 词：无铅焊料 应变率敏感性 纳米压入 力学性能 

分 类 号：TN383[电子电信—物理电子学]