Effect of solid solution treatment on adiabatic shear bands of extruded Mg-6Zn-1Cu-0.6Zr alloy

• Published in: Journal of alloys and compounds 2025-01, Vol.1010, p.177503, Article 177503
• Main Authors: Wang, Zhi, Xu, Chenkun, Zhu, Ran, Zhou, Le, Wang, Feng, Zhang, Weihan, Wei, Ziqi, Mao, Pingli
• Format: Article
• Language: English
• Subjects: Adiabatic shear bands; Adiabatic shear sensitivity; Dynamic recrystallization; ZG61 magnesium alloy
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.177503

The adiabatic shear bands (ASBs) mechanism and adiabatic shear sensitivity of extrusion shearing Mg-6Zn-1Cu-0.6Zr (ZC61) alloy before and after solid-solution treatment are studied at 200 °C and strain rate of 2100 s−1 using electron backscattered diffraction (EBSD) and transmission electron microscope (TEM) techniques. The experimental results show that {101̅1}-{101̅2} contraction-extension secondary twinning mechanism with high critical resolved shear stress (CRSS) provides sufficient energy for the formation of adiabatic shear bands in extrusion shearing ZC61 alloy and solid solution treatment ZC61 alloy. In addition, the accumulation of dislocations in precipitated phases and the bulging of grain boundary are also reasons for promoting the formation of dynamic recrystallization in the shear band region. Meanwhile, the solid solution treatment effectively reduces the adiabatic shear sensitivity of extrusion-shearing ZC61 alloy due to the lattice distortion caused by the dissolved Zn element, which increases the CRSS of basal slip, leading to improve the intrinsic plasticity of material after solid solution treatment. •The microstructure of adiabatic shear bands and the similarities and differences of shear band formation mechanism of ZC61 alloy before and after solution treatment were analyzed by EBSD technique.•The proportion of recrystallization and the proportion of twin boundary in ASB of two kinds of alloy before and after solution treatment were calculated respectively, and the effect of solution treatment on the formation mechanism of adiabatic shear band and the adiabatic shear sensitivity of ZC61 magnesium alloy was analyzed.•Based on the adiabatic shear sensitivity coefficient formula, the adiabatic shear sensitivity coefficient was calculated to judge the change of adiabatic shear sensitivity of ZC61 magnesium alloy before and after solution treatment.