Application of the Hardening Law in the Multiscale Simulation for Superplastic Deformation

Author of the article:HAN Xiaoning1 , YANG Junzhou2 , WU Jianjun2 , LI Jinshan1

Author's Workplace：1. School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, China; 2. School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China

Key Words：superplastic deformation; numerical simulation; strain compensation; constitutive model; titanium alloy

Abstract：To improve the precision of multiscale numerical simulations for the superplastic formation of TC4 alloys, the hardening law of metal materials at high temperatures was investigated. Based on the flow behavior of high-temperature tensile tests, a simple model considering strain hardening and softening was proposed. Then, the established model was applied to the multiscale numerical simulation of superplastic forming. The results show that the strain compensation model can be employed to describe the flow behavior of TC4 titanium alloy during superplastic deformation. In addition, comparing the simulated results of microscale variables such as grain size and cavity volume fraction with the calculated results of a multiscale physically based constitutive model, it can be concluded that the proposed method could be effective for the numerical simulation of flow stresses and microstructure evolution during hot deformation.