真空重熔对Mg-Gd-Y-Nd/SiC_P复合材料组织与性能的影响  

Effects of Vacuum Re-melting on Microstructure and Mechanical Properties of Mg-Gd-Y-Nd/SiC_P Composite

作　　者：邓运来[1] 官立群[1] 刘钊扬[1] 吴懿萍[1] 仲莹莹[2] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]中国航天科工防御技术研究试验中心,北京100854

出　　处：《热加工工艺》2013年第10期1-6,共6页Hot Working Technology

基　　金：国家重点基础研究发展计划资助项目(2010CB731700)

摘　　要：采用金相显微镜(OM)、扫描电镜(SEM)及其附带的能谱仪(EDS)和拉伸试验等技术研究了经搅拌铸造与真空重熔铸锭-挤压制备的Mg-Gd-Y-Nd/SiCP复合材料的显微组织与力学性能。结果表明,搅拌铸造法制备的铸锭经真空重熔凝固后,晶粒粗大,SiCP重新聚集,有利于排出搅拌铸造吸入的气体,这些组织特征对后续挤压棒材具有冶金遗传影响,使挤压棒获得更高强度。但较大的晶粒与第二相纤维组织降低了伸长率。SiCP颗粒会与Gd、Y元素反应生成REmSin相,但其不足以弥补因此而损失的Gd、Y元素的析出相强化,以及SiCP对杨氏模量的增强效果。The microstructure and mechanical properties of Mg-Gd-Y-Nd/SiCp composite fabricated by stirring casting and vacuum re-melting were investigated by OM, SEM, EDS and tensile test. The results show that the vacuum re-melting results in the increase of grain size, and the re-aggregation of SiCp, and the absorbed gas during the stirring casting discharges. These microstructure has genetic effects on the extruded material, which can make the increase of strength and the decrease of elongation of the material. REmSin particles can be formed by reaction between SiCp and rare earth elements of Gd and Y. However, the strength effect of REmSin particle is not enough to cover that of the loss precipitation particles including the elements of Gd and Y, and the reinforcement of SiCp to Young＇s modulus.

关 键 词：镁合金 SiCp粒子 复合材料 真空重熔 

分 类 号：TG292[金属学及工艺—铸造] TB331[一般工业技术—材料科学与工程]