Regular Article

Implementation issues of Yld2000-2d model under larger biaxial yield stress

School of Mechanical Engineering, Tongji University, No. 4800 Caoan Road, Shanghai 201804, PR China

^* e-mail: sun1979@sina.com

Received: 12 January 2018
Accepted: 4 June 2018

Abstract

In the field of sheet forming simulation, yield models serve as one of the most crucial factors for accurate computational results, and plane stress yield models have the capacity for both high efficiency and high accuracy. During recent years, applications of the Yld2000-2d model to sheet forming simulation of steel and aluminum have become increasingly popular due to its outstanding ability in describing these materials’ yield phenomena. For the computational implementation of this model, the Newton–Raphson iteration can correctly obtain the solutions of return mapping equations in most cases. However, it has been found in this work that the traditional iteration process may fall into a convergence problem when the yield stress is prominent (σ_b/σ₀ > 1.2). To solve the new finding problem, a line search algorithm is added to the Newton–Raphson iteration process. Biaxial tension simulation results show that the line search algorithm could converge successfully even when σ_b/σ₀ = 1.4. The simulation of the Erichsen test shows the applicability of the established Yld2000-2d model combined with a line search algorithm in the Newton–Raphson iteration process.