Effect of Heat-Treatment Time on Microstructure and Mechanical Properties of Mg-5Gd-2Y-2Zn-0.5Zr Alloy

Abstract:

Microstructure evolution of Mg-5Gd-2Y-2Zn-0.5Zr alloy during high temperature heat-treatment at 500°C in the time range 10-70h was investigated. The results show that after adding the element Y, the as-cast Mg-5Gd-2Y-2Zn-0.5Zr alloy forms the Mg12Zn(Y,Gd) phase with 18R-LPSO structure at the grain boundary. During heat-treatment at 500°C, the stability of 18R-LPSO structure is weakened by Gd atoms, parts of LPSO phases dissolve gradually into the matrix with time prolonged and a new type Mg(Y,Gd)Zn phase come into being. LPSO phase in the grain boundary can ensure the ultimate tensile strength and elongation of the alloy, and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase results the decrease of UTS and elongation.

• Periodical: Advanced Materials Research (Volumes 482-484)
• Pages: 1384-1389
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.482-484.1384
• Online since: February 2012
• Authors: Ling Gang Meng, Can Feng Fang, Peng Peng, Nai Pu Li, Qiong Zhu, Xing Guo Zhang
• Keywords: Heat-Treatment Time, LPSO Phase, Mechanical Property, Mg-Gd-Y-Zn-Zr Alloy, Microstructure

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