Edge crack and anisotropy of mechanical properties of AZ31 magnesium alloy under high strain rate rolling

doi:10.13251/j.issn.0254-6051.2020.01.036

Abstract

Abstract: High strain rate rolling was carried out on as-casting AZ31 magnesium alloys over the temperature ranges 300 to 400 ℃ with average strain rates of 10-29 s ^-1. The edge cracks, microstructures and anisotropy of mechanical properties were investigated. The results show that with increasing the average strain rate, edge crack is improved. The change of edge crack length at 300 ℃ is more obvious than that at 350 ℃ and 400 ℃. Affected by the temperature rise and average strain rate, the grain size does not decrease, but fluctuates with average strain rate increasing. At a relatively low strain rate, the anisotropy of the sheet is obvious due to the existence of enlongated grains. With the increase of the average strain rate, the amount of enlongated grains decreases and the microstructures are gradually uniform, which can be attributed to the complete recrystallization. Finally, the anisotropy of the sheet is improved. The ductile fracture is the main fracture mechanism for the rolled sheet.

Key words: AZ31 magnesium alloy, high strain rate rolling, edge crack, microstructure, anisotropy

CLC Number:

TG146.2

Liu Xiao, Wang Yangyang, Zhu Biwu, Sun Youping, Yang Hui, Tang Changping. Edge crack and anisotropy of mechanical properties of AZ31 magnesium alloy under high strain rate rolling[J]. HTM, 2020, 45(1): 181-187.

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