Sn-3.5Ag-2Bi-0.7Cu无铅焊料压入蠕变性能的研究

Research on Indentation Creep Property of Sn-3.5Ag-2Bi-0.7Cu Lead-Free Solder

摘要:

对Sn-3.5Ag-2Bi-0.7Cu无铅焊料在温度为50~100 ℃，应力为16.7~43.2 MPa条件下的压入蠕变性能进行研究。得到压入蠕变的应力指数n=3.181、蠕变激活能Q=59.189 kJ/mol、材料的结构常数A=0.423。获得Sn-3.5Ag-2Bi-0.7Cu无铅焊料稳态压入蠕变速率本构方程：=0.423σ3.181exp（–59189/RT）。随着温度和应力的增加，Sn-3.5Ag-2Bi-0.7Cu无铅焊料的压入蠕变速率明显增加，蠕变后Ag3Sn、Cu6Sn5相明显变粗变短。A

Abstract:

The indentation creep behaviour of Sn-3.5Ag-2Bi-0.7Cu lead-free solder was studied in the temperature range of 50-100 ℃ and indentation stress range of 16.7-43.2 MPa. The stress exponent n of 3.181, creep activation energy Q of 59.189 kJ/mol, and material structural constant A of 0.423 were obtained. The constitutive equation of the steady state indentation creep rate of the Sn-3.5Ag-2Bi-0.7Cu lead-free solder was =0.423σ3.181exp(–59189/RT). The experiment shows that the indentation creep rate increased dramatically as the temperature and stress increased. The Ag3Sn and Cu6Sn5 phases became coarser and shorter after indentation creep, which could increase indentation creep resisting property by strengthening β-Sn matrix.