【摘要】 采用经钝化处理的SiC颗粒作为增强体制备的SiCp／LD2复合材料、与普通SiCp／LD2相比，材料明显提高了塑性有限元与拉伸断口的扫描电镜（SEM）分析表明．材料经T6处理后。断裂机制以颗粒断裂为主，塑性得以提高的原因主要是颗粒尖角钝化后、降低了尖角处热残余应变集中。并降低了颗粒尖角部在外加应变较低时断裂的可能性.而材料未经T6处理时，断裂机制以基体失效为主．塑性提高主要源于尖角处热残余应变集中的降低，因而经T6处理的复合材料塑性提高的幅度大于挤出态复合材料更多还原

【Abstract】 Blunted SiC particles were selected as reinforcement to fabricate SiC./LD2 composites. Compared with a general SiC particle,the blunted SiC. reinforced composite has higher ductility.Analysises of finite element method(FEM) and tensile fractographic scanning electron microscope(SEM)show that particle fracture is the main failure mechanism of composites after T6 treatment.The ductility improvement of processed SiCp/LD2 is attributed to decrease the heat-residual-strain concentration near penetrating particle corner and the possibility of penetrating particle corner fracturing at low level of external strain when the penetrating particle corner has been blunted. The main failure mechanism of composites after extruded but no T6 treatment is matrix failure. Therefore, extent of ductility improving of composites after T6 treatment is higher than that of composites after extruded.更多还原