Abstract
To accurately evaluate the strength reliability of solder joint by FEM analysis, the method to evaluate the creep distribution of solder joints in-situ must be developed. The indentation creep test is an effective method to evaluate the creep distribution of solder joints in-situ. However, the stress calculated using this method is overestimated when compared with that obtained by tensile creep test using bulk specimen. In this paper, a new indentation test to evaluate the creep deformation using a new reference area was proposed. The proposed method provided the same stress as that obtained by tensile creep test This method consists of two kinds of indentation tests. The first test is maintaining the indentation depth constant at different depths and the second is an indentation creep test where a constant load is maintained for various loads. Assuming the specimen of this research is Sn-3.0Ag-0.5Cu solder alloy, the feasibility of this method was confirmed using FEM analysis. As a result, a new reference area appropriate for the indentation creep test was defined. At the same time, the same evaluation result as that obtained by tensile creep test was provided by the indentation creep test considering new reference area. Hence, it will be possible to evaluate the steady-state creep deformation of the new material by this evaluation method.
