【摘要】 材料的强韧性与材料的耐磨性密切相关。本文研究了氧化锆增韧氧化铝陶瓷颗粒(ZTA_p)增强金属基复合材料的强度、韧性以及断裂机理,为改善ZTA_p增强金属基复合材料耐磨性提供参考依据。首先通过真空烧结技术制备了不同粒径与不同体积分数的ZTA_p/Fe45复合材料,测试了复合材料的拉伸性能、弯曲性能与冲击韧性,采用扫描电镜(SEM)观察了复合材料的断口,分析了复合材料的断裂机制。结果表明:ZTA_p的加入使复合材料的强度降低、韧性提高。随着ZTA_p体积分数增加,复合材料的抗弯强度逐渐降低;ZTA_p粒径增大,复合材料的冲击韧性先增加后降低,ZTA_p粒径为2.0 mm与2.5 mm(F14与F12)复合材料的冲击韧性高于Fe45基体。ZTA_p/Fe45复合材料的断口为脆性断裂,其中Fe45基体的断裂机理为解理断裂;ZTA_p主要有2种失效形式:颗粒断裂和颗粒脱粘拔出。更多还原

【Abstract】 The strength and toughness of materials are closely related to the wear resistance of materials.In this paper,the strength and toughness and fracture mechanism of zirconia toughened alumina ceramic particles(ZTA_p)reinforced metal matrix composites were studied to provide reference for improving the wear resistance of ZTA_p reinforced metal matrix composites.Firstly,ZTA_p/Fe45 composites with different particle sizes and different volume fractions were prepared by vacuum sintering technology.The tensile properties,bending properties and impact toughness of the composites were measured.The fractures of the composites were observed by scanning electron microscope(SEM)to analyze the fracture mechanism of the composites.The results show that the addition of ZTA_p reduces the strength of the composites,but increases the toughness of the composites.As the volume fraction of ZTA_p increases,the flexural strength of the composites decreases gradually.The impact toughness of the composites first increases and then decreases with the increase of ZTA_p size.The impact toughness of ZTA_p/Fe45 composites with particle sizes of 2.0 mm and 2.5 mm(F14 and F12)is higher than that of Fe45 matrix.The fracture of ZTA_p/Fe45 composites is brittle fracture,in which the fracture mechanism of Fe45 matrix is cleavage fracture.ZTA_p mainly have two failure forms,namely particle fracture and particle debonding and pulling out.更多还原