超高压下Mg-6Zn-1Y合金的凝固组织与性能  

Microstructure and mechanical properties of Mg-6Zn-1Y alloy solidified at high pressure

作　　者：董允[1] 林小娉[1] 徐瑞[2] 郑润国[1] 叶杰[1] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110819 [2]燕山大学材料科学与工程学院,河北秦皇岛066004

出　　处：《材料热处理学报》2013年第10期73-77,82,共6页Transactions of Materials and Heat Treatment

基　　金：辽宁省自然科学基金(20112063);河北省自然科学基金(E2010001398)

摘　　要：利用SEM、EDS、XRD研究了超高压凝固下Mg-6Zn—Y合金的凝固组织及性能。结果表明，常压下Mg-6Zn·1Y合金的宏观凝固组织为粗大的树枝晶，二次枝晶间距约为40～50μm；在GPa级超高压凝固条件下，合金的凝固组织显著细化，6GPa-1300℃凝固条件下，其二次枝晶间距仅为3～6μm；超高压下凝固的合金基体上分布的粒状相更加细小和均匀弥散，单位面积上粒状相的数量显著增多。常压下合金的显微硬度为59HV，在6GPa下超高压下合金的硬度大幅提高，达到85HV。高压下合金的弹性模量由常压下的68GPa减小到6GPa下的59GPa。Microstructure and mechanical property of solidified Mg-6Zn-IY alloy at super-high pressure of 2 -6 GPa were investigated by SEM, EDS and XRD. The results show that the microstructure of the solidified Mg-6Zn-IY alloy at normal pressure consists of coarse dendrite with the secondary dendritic arm spacing of 40 - 50μm, however, under the super-high pressure, the microstructure of the solidified Mg-6Zn-IY alloy is significantly refined. The secondary dendritic arm spacing is only 3 -6 μm in the solidified alloy at 1300℃ with the pressure of 6 GPa. The granular phase distributed on matrix of the solidified alloy under super-high pressure is more fine and uniformly disperse, and the number per area of the granular phase remarkably increases. The microhardness of the solidified alloy under ambient pressure is 59 HV, but the microhardness of the alloy at 6 GPa greatly increases due to the refinement of the dendrite, and reaches 85 HV. The elastic modulus decreases from 68 GPa of the alloy at ambient pressure to 59 GPa of the alloy at 6 GPa.

关 键 词：GPa级超高压 Mg-6Zn-1Y合金 显微组织 性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程] O521.2[金属学及工艺—金属材料]