复合铸造SiCp／ZL104复合材料组织性能研究

Research on Microstructure and Mechanical Properties of SiCp/ZL104 Composites Fabricated by Compound Casting

采用复合铸造法制备出平均粒径为15.8μm、体积分数为20%的SiC颗粒增强工业用ZL104铝合金基复合材料。对实验制备的颗粒增强铝基复合材料试样的微观组织结构、力学性能进行了研究。实验结果表明,所制备的复合材料中SiC增强颗粒分布均匀,界面层较薄且有明显的溶质扩散;复合材料试样的孔隙率为4.2%,硬度达到76.2HB,抗拉强度达到135MPa,伸长率为0.5%。经过断口分析发现,复合材料主要表现为增强体颗粒附近基体铝合金的韧性断裂,材料性能的降低是由于复合材料的孔洞缺陷割断了材料的连续性,引起局部应力集中,从而产生裂纹而断裂。

The ZL104 composites reinforced by 20% SiCp （volume fraction） was fabricated by compound casting process, and the average diameter of SiC particles was about 15.8 Ixm. The microstructure and mechanical properties of the samples prepared by SiCp/ZL104 Composites were researched. The test results show that there is a reasonable uniform dispersion of particles in the matrix alloy, and the interface between reinforced particles and the matrix is thin with gradual changes of solute atom. The porosity, brinell hardness, tensile strength and elongation of the samples are 4.2%, 76.2 HB, 135 MPa and 0.5% respectively. The tensile fractograph analysis show that the casting defects of apertures destroy the connection of components in composites, the tensile fracture bring on the fracture of the matrix alloy.