Effect of die parameters and coefficient of friction on equivalent plastic strain during ECAE: modeling and optimization

Abstract

The present study investigates the effect of die parameters and the coefficient of friction on the equivalent plastic strain (PEEQ) during Equal Channel Angular Extrusion (ECAE). The purpose is to optimize the die parameters to enhance material flow, strain distribution, and overall efficiency of the ECAE process. The study includes an analysis of three critical die parameters: channel angle (ϕ), corner angle (ψ), and coefficient of friction (µ) where each parameters are evaluated at three different levels using the Taguchi-based L9 orthogonal array. The main objective is to identify optimal conditions that balance material deformation and tool wear, addressing issues related to non-uniform strain and defects caused by improper parameter settings. Finite element analysis (FEA) using ABAQUS/CAE software was employed to simulate the deformation behavior of wrought Mg alloy-AZ80 under various die configurations for a single-pass ECAE process. The results indicated that increasing channel and corner angles decreased PEEQ, whereas higher friction coefficients increased PEEQ. Optimal settings were identified as ϕ = 110°, ψ = 10°, and µ = 0.15, which maximized the PEEQ. The study concludes that adjusting die parameters and friction coefficients significantly impacts the efficiency and outcomes of the ECAE process, with the potential to produce high-quality ultrafine-grained materials through optimized conditions. The findings provide valuable insights for improving ECAE practices in industrial applications.

Keywords

• Die parameters
• friction coefficient
• plastic strain
• channel angle
• corner angle
• finite element analysis