Mohammad Motalab

TL;DR: The Anand viscoplastic constitutive model is often used to represent the deformation behavior of solders in electronic assemblies as mentioned in this paper, and the nine parameters of the Anand model are typically determined from uniaxial stress-strain tests at several strain rates and temperatures using a standard multistep model parameter determination procedure.

TL;DR: In this article, a revised set of viscoplastic stress-strain relations for solder that include material parameters that evolve with the thermal history of the solder material is presented. And the effects of aging on the nine Anand model parameters have been examined by performing stressstrain tests on SAC305 samples that were aged for various durations (0-6 months) at a temperature of 100 C.

TL;DR: In this article, a new finite element based prediction procedure was developed that utilizes constitutive relations and failure criteria that incorporate aging effects, and then validated the new approach through correlation with thermal cycling accelerated life testing experimental data.

TL;DR: In this article, the authors adapted the Anand viscoplastic stress-strain relations for Pb-free solders to include material parameters that evolve with the thermal history of the solder material.

TL;DR: In this paper, the effects of aging on lead free solder material behavior were explored and new reliability prediction procedures were developed to predict the reliability of solder joints in assembly subjected to aging prior to field use.