Microstructure and Kinetics of β-Mg₁₇Al₁₂ Phase Transformation for Warm Rolled AZ91 Magnesium Alloy

Abstract:

The microstructure and the kinetics of β-Mg₁₇Al₁₂ phase transformation during annealing process for warm-rolled AZ91 magnesium alloy were investigated. The results showed that few twins were found in solid state AZ91 magnesium alloy after warm rolling, which provides energy for β-Mg₁₇Al₁₂ particles to nucleate and growth; the β-Mg₁₇Al₁₂ particles were prior to form at α-Mg, twin grains boundary and especially the place of high energy; by the annealing time extending, the quantity of β-Mg₁₇Al₁₂ particles increased. And combined with the experimental data and the JMAK equation, the fitting equation of Kinetics of β-Mg₁₇Al₁₂ phase transformation was built. During annealing process, the twin grains disappeared and the original bulky organization was replaced by recrystallization grain, while the grain refinement was obvious with the grain reduction to 20-60μm.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 421-425
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.421
• Online since: February 2013
• Authors: Lin Yang, Jun Dong Wang, Si Ni Wang, Li Lin, Zheng Liu
• Keywords: Rolling , Annealing, AZ91 Magnesium Alloy, Kinetics of β-Mg₁₇Al₁₂ Phase, Microstructure

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