Effect of heat treatment on LPSO morphology and mechanical properties of Mg-Zn-Y-Gd alloys

• 作者: Hongxin Liao Jonghyun Kim Taekyung Lee Jiangfeng Song Jian Peng Bin Jiang Fusheng Pan
• 来源期刊: 镁合金学报(英文)
• 学科: 工学
• 关键词: Mg alloy LPSO Age behavior Mechanical properties Heat treatment Strengthening efficiency
• 年，卷（期）: 2020,（4）
• 页码范围: 1120-1127
• 页数: 8页
• 分类号: TG1

摘要

The mechanical properties and microstructure were investigated under different Zn content and heat treatment conditions in a Mg-Zn-YGd cast alloy.A part of the long period stacking order(LPSO)phases transformed to W-M^ZnaRE?phases with an increase in Zn content from 0.9 at.%to 1.8 at.%,and the ultimate tensile strength(UTS)increased from 229 MPa to 248 MPa.With solution treatment at 480°C,the content of the LPSO phase and strength sharply decreased in the Mg-1.8Zn-0.8Y-0.8Gd alloy,whereas this change was not significantly observed in the Mg-0.9Zn-O.8Y-O.8Gd alloy.After solution treatment,the elongation significantly improved and the UTS sharply decreased in both alloys.The lamellar and filminess LPSO phases were observed with aging treatment at 200℃.Moreover,the strengthening efficiency of lamellar and filminess LPSO phases was lower than that of the block LPSO phases.Therefore,the UTS of the T6 state was lower than that of the as-cast alloy.