Comparison of Cyclic Inelastic Features of a Lead-Free Solder Alloy and a Nickel-Base Superalloy

Abstract

In this study, a time-dependent constitutive model with nonlinear kinematic hardening is applied to simulating the cyclic inelastic behavior of a lead-free solder alloy Sn-3.0Ag-0.5Cu at room temperature and a nickel-base superalloy IN738LC at 850˚C. The development of kinematic hardening is assumed to consist of strain hardening and power-law dynamic recovery. Then, by simulating the hysteresis loops of stress and strain under cyclic loading, it is shown that the nonlinearity in the dynamic recovery of kinematic hardening strongly influences the Bauschinger effect in simulated cyclic inelastic behavior, and that the Bauschinger effect of Sn-3.0Ag-0.5Cu is much weaker than that of IN738LC. It is thus demonstrated that quicker evanescence of anisotropic hardening renders the Bauschinger effect less significant.