Superplastic Forming Limit and Instability of AZ31B Sheet

Abstract:

The superplastic bulging test of AZ31B magnesium alloy sheet of 0.6mm thick was carried out on Alliance RT/50 tensile machine at 573K and 3.3×10^-4S^-1. It is found that either in tensile-compressive deformation or in bi-axis tensile deformation, the judgment criterion for local necking of superplastic deformation is dε₂=0. The superplastic forming limit diagram(FLD) at 573K and 3.3×10^-4S^-1 was established for the first time.

• Periodical: Materials Science Forum (Volume 686)
• Pages: 343-347
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.686.343
• Online since: June 2011
• Authors: Mei Juan Song, Ling Yun Wang, Rao Chuan Liu
• Keywords: AZ31B Magnesium Alloy, FLD, Plastic Instability, Superplastic

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