抄録
To evaluate the strength reliability of electronic substrate by the accurate structural analysis, the method to evaluate the creep deformation of in-situ solder joints must be developed. The Indentation creep test is one of effective method to evaluate the creep deformation in microscopic specimen. It is required that the result obtained by the indentation creep test is should be expressed by the constitutive equation for the creep deformation under the uniaxial stress evaluated by the tensile creep test In this paper, the indentation creep test at IN loading for 9000s duration is conducted by experiment and the result obtained by the indentation creep test is compared with that obtained by the tensile creep test using the bulk specimen. As the result, the result obtained by the indentation creep test did not coincide with that obtained by the tensile creep test To explain the difference, the numerical indentation creep test is conducted. Finally, the method to determine the suitable reference area for calculating uniaxial stress of the indentation test is proposed. The reference area determined by the new indentation test is the effective to obtain the reasonable creep curves by the indentation test.
