Superplastic Instability and Damage Evolution of AZ31B Magnesium Alloy Shee

Abstract:

Superplastic instability and damage evolution of AZ31B magnesium alloy sheet were investigated in this paper. Maximum elongation of 216% and strain rate sensitivity of 0.36 were obtained at 723k and a strain rate of 1×10^-3s^-1, whose fracture was due to the growth and interlinkage of cavities that nucleated at grain boundary. After superplastic tensile tests and quantitative analysis of cavity volume fraction, A cavity growth model were established, and the damage evolution equation based on the law of the micro-damage evolution and statistical mechanics was derived out, and damage characteristic parameters as well as the critical value of damage variable were identified so as to provide a theoretical ground on which the plastic forming technology of magnesium alloy sheet can be optimized.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 451-458
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.451
• Online since: April 2015
• Authors: Mei Juan Song*, Chuan Hui Huang, Min He, Xiao Dong Luo, Ya Mei Wu
• Keywords: AZ31B Magnesium Alloy, Cavity, Damage Evolution, Superplasticity

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