Grain Growth Behavior of AlMg5 Alloy Fabricated by Using a New Mg Mother Alloy Containing Al₂Ca during Homogenization and Hot Compression

Abstract:

Grain growth behavior of AlMg5 alloy fabricated by using a new Mg mother alloy containing Al₂Ca (referred to as AlMg5-Al₂Ca hereinafter) was investigated during homogenization and subsequent hot compression test. Normal AlMg5 alloy using a commercial Mg mother alloy showed abnormally grown large grains in its microstructure after homogenization at 520 ̊C for 12hrs, while the grain growth in the AlMg5-Al₂Ca alloy was completely suppressed by formation of stable Al₄Ca during solidification on grain boundary. The compressive flow stress of normal AlMg5 alloy at 400 ̊C was significantly increased after homogenization because of lack of grains having proper slip directions to the applied load. But the flow stress of AlMg5-Al₂Ca alloy showing no grain growth during homogenization was slightly decreased implying lower energy needed for subsequent thermo-mechanical processing.

• Periodical: Materials Science Forum (Volume 877)
• Pages: 328-333
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.877.328
• Online since: November 2016
• Authors: Bong Hwan Kim*, Young Ok Yoon, Shae K. Kim
• Keywords: Al-Mg, Aluminium Alloy, Grain Growth, Homogenization, Hot Compression

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