不同粒度SiC_P增强铜基复合材料拉伸性能及断裂机制的研究

Research on tensile properties and fracture mechanism of different sizes SiCP reinforced Cu matrix composites

以不同粒度SiCP和电解铜粉为原料,采用粉末冶金工艺制备了SiCP增强Cu基复合材料。研究了SiCP和基体铜粉粒度的变化对材料拉伸性能和断裂机制的影响。结果表明,在基体铜粉粒度为44μm时,10μm的SiCP增强复合材料的抗拉强度达到最大值,为265.7MPa,其断裂机制是以Cu-SiC界面处基体撕裂为主,而当SiCP粒度为2μm时,由于分散不均匀、团聚等原因使得材料强度降低。大粒度SiCP(>10μm)增强复合材料由于界面面积有限和增强颗粒间距过大,使得增强效果有限,其断裂机制是以Cu-SiC界面脱粘和SiCP解理开裂为主。实验证实了在SiCP增强铜基复合材料中基体和增强颗粒粒度存在着最佳配比关系可使复合材料达到最佳增强效果。

With various sizes SiCp and electrolysis copper powder as a raw material, the copper matrix composites reinforced by SiCp were fabricated via powder metallurgy method. The effect of different sizes SiCp and copper on the tensile properties and fracture mechanism of Cu/SiCp composites were investigated. The results show that the tensile strength of composites with 10μm SiCp attains the biggest value, is 265.7MPa, and their breakage is due to tearing of matrix near Cu-SiC interface when matrix is 44μm electrolysis copper powders. However,The tensile strength of composites with 2μm SiCp falls because SiCp particles are difficult to disperse even and reunite phenomenon happen. Composites with large partiele（10μm）possess finite strength owing to interfaeial area limited and the space between SiC particles larged,and interracial debonding and SiC cleavage crack have a prominent effect on the failure mechanism of composites. Experiment indicates that particle reinforced Cu-matrix composites have the best reinforcement effect when optimal matching between matrix and reinforced particles is founded.