(湖南大学 材料科学与工程学院，长沙 410082)
摘 要: 采用Bc路径对超高强铝合金基复合材料7090/SiCp进行等径角挤压加工。采用金相显微镜、力学性能测试及扫描电镜，分析该复合材料的显微组织和力学性能。结果表明：经过4个道次的等径角挤压加工，该复合材料的晶粒逐渐被细化，第三道次后晶粒尺寸达到1 μm以下；继续进行等径角挤压时，晶粒未发生明显变化。室温拉伸结果显示：晶粒的抗拉强度逐渐增大，在第三道次下道次间抗拉强度的增加幅度最大，达到14.3%，此时其抗拉强度及伸长率分别为338.57 MPa及15%；SiC颗粒在大的剪切力作用下被破碎细化，在基体中的分布也更加均匀。
关键字: 铝基复合材料；SiC；等径角挤压；显微组织；力学性能
（College of Materials and Engineering, Hunan University, Changsha 410082, China）
Abstract:The structures and properties of 7090/SiCp Al matrix composites were studied by severe plastic deformation through Bc route equal channel angular pressing (ECAP). Equal channel angular pressing was performed on an ultra-high strength 7090/SiCp aluminum alloy matrix composite. By optical microscopy, mechanical tensile test and scanning electron microscopy, the microstructures and mechanical properties of 7090/SiCp composite were discussed. The results show that the size of the composites is fined gradually, and the finest grains are obtained of less than 1 μm after 3 passes of ECAP. However the grains do not change after the 4th pass of ECAP. The tensile strength increases gradually with the addition of pass at room temperature, and the increasing degree between two passes achieves the maximum at the third pass, is 14.3%, and the ultimate tensile strength and elongation are 338.57 MPa and 15%, respectively. SiC particles are broken under high shearing stress, and the particle distribution in the matrix alloy is homogeneous.
Key words: aluminum matrix composite; SiC; equal channel angular processing; microstructure; mechanical properties
ISSN 1004-0609
CN 43-1238/TG
CODEN: ZYJXFK
ISSN 1003-6326
CN 43-1239/TG
CODEN: TNMCEW