the creep parameters of sac305 unleaded solders

The tensile and shear loading creep parameters of unleaded Sn/3.0Ag/0.5Cu solders are extracted from the proposed tensile and shear creep tests in this work. Four creep loading temperatures, that is, , , , and C, are employed to extract the corresponding parameters. The creep parameters for tensile and shear loading models, that is, stress exponent, material constant, and activation energy, are curve-fitted by using the least square error and simplex optimization algorithms. The accuracy of the extracted parameters correlated with the measured strain rate versus temperature curves. Results indicate that the proposed measurement setup and extraction algorithm is feasible to extract the tensile and shear type creep parameters with good accuracy.