The modified temperature term on Johnson-Cook constitutive model of AZ31 magnesium alloy with {0002} texture

• Published in: Journal of magnesium and alloys 2020-03, Vol.8 (1), p.172-183
• Main Authors: Zhang, Feng, Liu, Zheng, Wang, Yue, Mao, Pingli, Kuang, Xinwen, Zhang, Zhenglai, Ju, Yingdong, Xu, Xiaozhong
• Format: Article
• Language: English
• Subjects: Adiabatic shear band; AZ31-ND with {0002} texture; Dynamic compression; Modified Johnson Cook constitutive model; Numerical simulation
• ISSN: 2213-9567; 2213-9567
• DOI: 10.1016/j.jma.2019.05.013

The dynamic compression experiments with Split-Hopkinson Pressure Bar(SHPB) were performed on AZ31 magnesium alloy rolled sheet specimens in the normal direction (AZ31-ND) with {0002} texture at the temperature of 293–523 K and the strain rate of 0.001–2200 s−1. The temperature term in Johnson-Cook(JC) constitutive model had been reasonably modified. This advantage made constitutive model promising for decribing the dynamic deformation behavior of AZ31-ND with {0002} texture more accurately. The obtained true stress-true plastic strain curves agreed well with the measured results in a wide range of strain rates and temperatures. The thermal softeninging, strain and strain rate hardening effect on the AZ31-ND with {0002} texture were discussed. The adiabatic shear band (ASB) of AZ31-ND with {0002} texture hat shaped specimen was successfully predicted by combining modified JC constitutive model and numerical simulation, which was also validated by Electron Back-Scattered Diffraction (EBSD) map under the same boundary condition.