复合材料的断裂行为
(1. 淮海工学院 机械工程系，连云港 222005；
2. 张家界航空工业职业技术学院 机械工程系，张家界 427000；
3. 淮海工学院 人事处，连云港222005；
4. 湖南大学 材料科学与工程学院，长沙 410082)
摘 要: 采用喷射沉积工艺制备SiCP/Al-11.7Fe-1.15V-2.4Si复合材料，并通过热压工艺对复合材料进行致密化，再通过热轧加工成板材。对复合材料的显微组织以及不同温度下复合材料的断裂性能和断口形貌进行研究。结果表明：采用热压致密后再热轧工艺能使SiC颗粒分布均匀，长轴方向平行于轧制方向，有利于增强复合材料的力学性能，复合材料的断裂性能和断面形貌与拉伸温度以及SiC的分布和取向相关，随着拉伸温度升高，SiC/Al界面强度减弱，拔断的SiC颗粒逐渐减少，SiC颗粒的拔出成为主要的裂纹源；与基体金属不同的是，复合材料的塑性随着温度升高而降低。
关键字: SiC颗粒；耐热合金；复合材料；喷射沉积；断裂行为
（1. College of Mechanical Engineering, Huaihai Institute of Technology, Lianyungang 222005, China;
2. Department of Mechanical Engineering, Zhangjiajie Institute of Aviation Industry Vocational,
Zhangjiajie 427000, China;
3. Department of Human Resource, Huaihai Institute of Technology, Lianyungang 222005, China;
4. College of Materials Science and Engineering, Hunan University, Changsha 410082, China）
Abstract:SiCP/Al-11.7Fe-1.15V-2.4Si composite was prepared by spray deposition and densified by hot pressing, and then were rolled into sheets. The microstructures, fracture properties and fractographies of the composite at different tensile temperatures were investigated. The results show that the uniform distribution of the SiC particles with their longitudinal direction parallel to the rolling direction is achieved by rolling after hot pressing, which contributes to the elevation of the mechanical properties of the composite. Fracture properties and fractographies of the composite are affected by the tensile temperature and distribution and orientation of SiC particles. The bonding between SiC particles and the matrix becomes weak, and the breakable particles reduce as the tensile temperature; the debonding of SiC/Al becomes the dominant fracture mechanism, the plasticity of the composite decreases as the tensile temperature increases, which is different from the matrix alloy.
Key words: SiC particle; heat resistant alloy; composite; spray deposition; fracture behavior
