低合金化Mg-Zn-Y合金的显微组织与力学性能  

Microstructures and Mechanical Properties of Low-Alloyed Mg-Zn-Y Magnesium Alloy

作　　者：李亚楠 聂凯波[1] 邓坤坤[1] 杨安 Li Yanan;Nie Kaibo;Deng Kunkun;Yang An(Shanxi Key Laboratory of Advanced Magnesium-based Materials,College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学材料科学与工程学院先进镁基材料山西省重点实验室,山西太原030024

出　　处：《稀有金属材料与工程》2021年第4期1425-1432,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51771129,51401144,51771128)。

摘　　要：通过常规铸造制备了3种成分的低合金化Mg-Zn-Y合金(Mg-0.6Zn-0.1Y、Mg-1.3Zn-0.1Y、Mg-2.0Zn-0.1Y,质量分数,%),并对其进行低温慢速挤压(140℃,0.1mm/s)。结果表明:随Zn含量的增加,挤压前合金的晶粒尺寸逐渐减小。挤压后合金晶粒显著细化,形成弥散的纳米析出相,同时随Zn含量的增加合金的再结晶程度与纳米析出相的数量均增加,基面织构强度则无显著变化。挤压后合金的力学性能得到大幅提升,其中Mg-2.0Zn-0.1Y合金的屈服强度、抗拉强度和延伸率分别达到406.4 MPa、424.53 MPa、12.2%。随Zn含量增加,Mg-Zn-Y合金的延伸率显著增加,其断口形貌由解理面转变为细小的韧窝,断裂方式由解理断裂转变为韧性断裂。Three kinds of low alloyed Mg-Zn-Y(Mg-0.6 Zn-0.1 Y, Mg-1.3 Zn-0.1 Y, Mg-2.0 Zn-0.1 Y, wt%) were prepared by conventional casting and then subjected to slow extrusion at low temperature(140 ℃, 0.1 mm/s). The results show that with the increase of Zn content, the grain size of the alloy before extrusion gradually decreases. After extrusion, the grains are significantly refined, forming dispersed nano-precipitated phases. At the same time, with the increasing the Zn content, the recrystallization degree of the alloy and the number of nano-precipitated phases increase, while the basal texture intensity exhibits unobvious change. The mechanical properties of the as-extruded alloys dramatically improve. The YS, UTS and EL of Mg-2.0 Zn-0.1 Y alloy are 406.4 MPa, 424.53 MPa and 12.2%, respectively. With the increase of Zn content, the elongation of Mg-Zn-Y alloy increases significantly, the fracture morphology changes from cleavage surface to tiny dimples, and the fracture pattern varies from cleavage fracture to ductile fracture.

关 键 词：MG-ZN-Y合金 低合金化 低温挤压 微观组织 力学性能 

分 类 号：TG146.22[一般工业技术—材料科学与工程]