One-Dimensional Macroscopic Constitutive Model for Ratcheting of Superelastic Shape Memory Alloys

Abstract

This paper presents a macroscopic constitutive model that is able to reproduce the uniaxial transformation ratcheting behaviors of the superelastic shape memory alloy (SMA) undergoing cyclic loading. A cosine-type phase transformation equation with the initial martensite evolution coefficient that helps to predict the residual martensite accumulation and the nonlinear features of the hysteresis loop with a small number of material parameters is established to describe the phase transformation behaviors of the SMA undergoing cyclic loading. The proposed model simultaneously takes into account the evolution of transformation-induced plastic strain during cyclic loading. The applied loading level and asymmetric tensile and compressive behavior of the SMA on transformation ratcheting are also considered in the proposed model. The evolutions of transformation ratcheting, transformation-induced plastic strain, and transformation stresses are constructed as the function of the accumulated residual martensite volume fraction. The simulated results are compared with the experimental results to show the validity of the proposed model in transformation ratcheting.