Microstructures and mechanical properties of a newly developed high-pressure die casting Mg-Zn-RE alloy

• 作者: Xiru Hua Qiang Yang Dongdong Zhang Fanzhi Meng Chong Chen Zihao You Jinghuai Zhang Shuhui Lv Jian Meng
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2020,（18）
• 页码范围: 174-184
• 页数: 11页
• 语种: 英文

摘要

A newly developed Mg-4Zn-2La-3Y alloy with high strength was fabricated by high-pressure die casting method,and its microstructures were thoroughly studied using transmission electron microscopy.The results demonstrate that it owns fine grains and approximately highly interconnected intermetallic phase skeletons,and exhibits ultra-high strength at both room and high temperatures.Interestingly,the eutectic intermetallic skeleton of this alloys is consisted of numerous fine particles,which are mainly consisted of two intermetallic phases,namely W and Mg12 RE.Multiple { 101 } twins and SFs were found in the Mg12 RE phase while a few of SFs in the W phase.Additionally,minor long-period stacking ordered phase was observed in the eutectoid phase,and it probably nucleated on the Mg12 RE phase following a certain OR as(0002)14H//(110)Mg12RE and[11(2)0]14H//[1(11)]Mg12RE,or (0002)14H//(211)Mg12RE and[11(2)0]14H//[1(11)]Mg12RE.This special intermetallic skeleton with many interfaces and planar faults can efficiently transfer dislo-cations across grain boundaries,and this is the key factor for the outstanding mechanical properties of the studied alloy.