Effect of Heat Treatment on Microstructures and Mechanical Properties of Extruded GWZ661 Alloy
ZHEN Rui1,2, SUN Yang-shan2, WANG Zhang-zhong1, FANG Xin-xian1, SHI Wei1
1. Department of Materials Science and Engineering,Nanjing Institute of Technology, Nanjing 211167,China;
2. Jiangsu Key Lab of Advanced Metallic Materials,School of Materials Engineering,Southeast University,Nanjing 211189,China
Abstract：A quaternary alloy with composition of Mg-6Gd-6Y-1Zn (mass fraction/%) was prepared by conventional casting and extrusion. The microstructure and aging behavior of the alloy were investigated. The results showed that the as-cast microstructure of the alloy consisted of the α-Mg matrix, Mg24(GdYZn)5 eutectic and Mg12Y1Zn1 phase. After extrusion the Mg12Y1Zn1 phase were stretched along the direction of extrusion, and the 14H-LPSO phase distributed between Mg12Y1Zn1 strips. Solid solution treatment at high temperature above 500℃ resulted in the dissolution of Mg12Y1Zn1 phase into the matrix and increase of the 14H-LPSO phase. When solution treated alloys was aged at temperature of 225℃ (T6 treatment), the 14H-LPSO phase and β' precipitated appear in microstructure. Aging of as extruded alloys (T5 treatment) also caused the formation of β' precipitates,however the volume fraction of 14H-LPSO phase was lower than that in specimens after T6 treatment. High tensile strength combined with good ductility was obtained from the alloy after T6-aging.
甄睿, 孙扬善, 王章忠, 方信贤, 石卫. 热处理对GWZ661变形镁合金组织与性能的影响[J]. 材料工程, 2012, 0(12): 39-44.
ZHEN Rui, SUN Yang-shan, WANG Zhang-zhong, FANG Xin-xian, SHI Wei. Effect of Heat Treatment on Microstructures and Mechanical Properties of Extruded GWZ661 Alloy. Journal of Materials Engineering, 2012, 0(12): 39-44.
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