采用放电等离子烧结法制备了碳纤维增强铜基复合材料CFs/Cu.利用光学显微镜、扫描电镜和万能试验机检测并分析了不同碳纤维长度对复合材料相对密度、显微结构及力学性能的影响.结果表明,添加质量分数为2.5％不同长度的碳纤维有利于提高CFs/Cu复合材料力学性能;但随着碳纤维长度增加,CFs/Cu复合材料相对密度下降,对力学性能的增强效果降低.添加1 mm长度碳纤维的复合材料相对密度和抗弯强度最佳,分别为99.34％和805.47 MPa,相较于未添加纤维的材料,其强度提升了65％;断口形貌显示为河流状花样和解理台阶特征,存在较少韧窝,属于以脆断为主,伴随少量韧性断裂的混合断裂机制.%Copper matrix composites ( CFs/Cu ) reinforced with short carbon fiber were prepared by spark plasma sintering. Effects of carbon fiber ( CF ) length on relative density, microstructure and mechanical properties of the composite were tested and investigated by optical microscope, scanning electron microscope and universal mechanical testing machine. Results showed that adding CFs of different length at an amount of 2.5％ was beneficial to the enhancement of composite mechanical properties. However, with an increase in the carbon fiber length, the relative density of CFs/Cu composite decreased and the enhancement of composite mechanical properties also slowed down. It is found that CFs/Cu composite with addition of 1 mm CF shows the best performance, with relative density and bending strength of 99.34％ and 805.47 MPa, respectively. The strength of the composite has improved by 65％ compared to the of composite without adding fiber. The fracture, with morphology of water blooms and cleavage of a "stair-step"appearance, consists predominantly of brittle fracture, accompanied with a little ductile fracture.
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