活塞用复合材料的制备和拉伸性能研究

通过对ＳｉＣＰ／ＺＬ１０９ 复合材料制备工艺的研究，成功地制备了晶粒细小、组织致密、缺陷较少且ＳｉＣ颗粒分布均匀的ＳｉＣＰ／ＺＬ１０９ 复合材料。同时，测试了该材料的拉伸性能，对拉伸性能提高（或降低） 的原因进行了探讨；采用扫描电子显微镜对材料的拉伸断口进行了观察，发现复合材料及未增强基体合金的断裂虽均属于塑性断裂与脆性断裂的混合型模式，但随着ＳｉＣ颗粒在复合材料中的体积分数增加，脆性断裂特征更为显著。

The Study on the Fabricating Technology and Tensile Properties of Composites for Piston

Through the testing of the fabricating technology for SiC P/ZL109 composites which will be used as piston materials,the SiC P/ZL109 composites were successfully fabricated which possess the microstructures with few casting defects and flaws,well distributed SiC particles in the matrix.The tensile properties of SiC P/ZL109 composites have been investigated.The reason for increasing or decreasing the tensile properties is analysed.SEM fractographic observations of the tested bars show that the failure of both the composites and the unreinforced matrix alloy is due to the mixed mode of ductlie fracture and brittle fracture,but the morphologic features of brittle fractures get more dominant with the increase of SiC particles.