Ag和Yb对Mg-6.0Gd-0.4Zr镁合金时效硬化和微观组织的影响  

Effect of Yb and Ag on age hardening and microstructure of Mg-6.0Gd-0.4Zr alloys

作　　者：周涛[1] 徐洪辉[1] 钟豪胤 肖华顺 ZHOU Tao;XU Hong-hui;ZHONG Hao-yin;XIAO Hua-shun(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]上海交通大学材料科学与工程学院,上海200240

出　　处：《材料热处理学报》2019年第12期19-24,共6页Transactions of Materials and Heat Treatment

基　　金：粉末冶金国家重点实验室自主课题

摘　　要：采用Ta坩埚真空封装法制备了9种Mg-Gd-Yb-Ag-Zr镁合金,利用显微硬度测试仪、扫描电镜(SEM)和电子探针显微分析(EPMA)等研究了Ag和Yb对Mg-6.0Gd-0.4Zr(GK6)镁合金时效硬化曲线和显微组织的影响。结果表明,Ag和Yb均能显著提高GK6镁合金的时效硬化,且两者同时加入的时效硬化效果更佳。在GK6-1.0Yb-1.0Ag和GK6-2.0Yb-1.0Ag镁合金中,观察到两个时效硬度峰,除颗粒状沉淀析出相外,还分别观察到了脊柱状和绒线状的时效析出相。在GK6-1.0Yb-0.5Ag镁合金中,观察到颗粒状沉淀析出相呈线型排列分布的现象。GK6-2.0Yb-1.0Ag、GK6-1.0Yb-1.0Ag和GK6-1.0Ag镁合金具有优异的时效硬化性能。Nine kinds of Mg-Gd-Yb-Ag-Zr magnesium alloys were prepared by Ta-crucible vacuum-sealing process. The effects of Ag and Yb on aging hardening curve and microstructure of the Mg-6.0Gd-0.4Zr(GK6) magnesium alloys were studied by means of microhardness tester, scanning electron microscopy(SEM) and electron probe microanalysis(EPMA). The results show that both Ag and Yb can significantly improve the aging hardening of the GK6 magnesium alloys, and the effect of aging hardening is better when both of them are added at the same time. In the GK6-1.0Yb-1.0Ag and GK6-2.0Yb-1.0Ag magnesium alloys, two age-hardening peaks are obviously observed, and in addition to the granular precipitated phases, the long spine-like and wool thread-like precipitates are also observed. In the GK6-1.0Yb-0.5Ag magnesium alloy, the phenomenon of linear arrangement and distribution of particle-shaped precipitated phases is observed. The GK6-2.0Yb-1.0Ag, GK6-1.0Yb-1.0Ag and GK6-1.0Ag magnesium alloys have excellent aging hardening properties.

关 键 词：稀土镁合金 时效硬化 沉淀析出 显微组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]