Cr变质对汽车驱动轴用Mg2Si/Al-Fe基复合材料组织和性能的影响  

Effects of Cr Modification on Microstructure and Properties of Mg2Si/Al-Fe Matrix Composites for Car Drive Shaft

作　　者：贾建波[1] 徐蓉[1] JIA Jianbo;XU Rong(Automotive Engineering Institute,Jingzhou Institute of Technology,Jinzhou 434200,China)

机构地区：[1]荆州职业技术学院汽车工程学院

出　　处：《热加工工艺》2018年第18期86-88,共3页Hot Working Technology

摘　　要：以Al-Fe合金为原材料,通过Mg-Si熔体直接反应制备Mg_2Si/Al-Fe基复合材料,研究Cr变质对复合材料组织中初始Mg2Si和富Fe相变质行为,以及拉伸性能和耐磨性的影响。结果表明：组织中生成了树枝晶Mg2Si相,针形相,以及共晶Si相与α（Al）相。通过Cr变质处理后,针形的β-Fe相转变为了骨骼形的α-Fe相,并且初生的Mg2Si相外形也变得更加规则,初生Mg2Si相尺寸减小31%。Cr变质处理后,复合材料的拉伸强度增加幅度达到14.8%,磨损性能增强了1.5倍,伸长率增加了50%。采用Cr变质处理后,试样拉伸断口部位生成了部分韧窝结构,出现了塑性断裂特征。Taking Al-Fe alloy as the raw material, Mg2Si/Al-Fe matrix composite was prepared by Mg-Si melt direct reaction. And the effects of Cr modification on the modification behavior of initial Mg2Si and rich Fe phase in microstructure of Mg2Si/Al-Fe matrix composite and the tensile properties, abrasion resistance were studied. The results show that, the microstructure is composed of Mg2Si dendritic phase, acicular phase, eutectic Si and α（Al） phases. After Cr modification treatment, the acicular phase transits to skeletal phase, and the appearance of primary Mg2Si phase becomes more regular, the size of primary Mg2Si phase decreases by about 31%. After Cr modification treatment, the tensile strength of the composites increases by 14.8%, the wear performance increases by 1.5 times and the elongation increases by 50%. After Cr modification treatment, the tensile fracture has some dimples and it shows plastic fracture characteristics.

关 键 词：复合材料 初生Mg2Si 力学性能 Cr变质 

分 类 号：TB333[一般工业技术—材料科学与工程]