【摘要】 本文对比研究了烧结、铸造亚共晶高铬铸铁和TM52钢结硬质合金在不同冲击功条件下的抗冲击磨粒磨损性能,利用扫描电子显微镜（SEM）观察分析磨损表面磨损形式及亚表层的微裂纹发展,开展磨损机制的分析探讨。结果表明,采用液相烧结技术制备的高铬铸铁具有优异的抗冲击磨粒磨损性能。烧结高铬铸铁在中、低冲击功条件下耐磨性能均明显优于TM52（4¹0倍）,在中、高冲击功工况下的耐磨性能相比铸造高铬铸铁提高10倍以上。烧结高铬铸铁的磨损机制主要是显微切削,当冲击功高时还会发生疲劳剥落磨损和脆性碎裂。烧结高铬铸铁中的短杆状M₇C₃型碳化物对金属基体的割裂和应力集中较小,而马氏体为主的基体具有高强韧性,能够有力地支撑和保持其中的碳化物均匀分散,阻滞微裂纹的萌生和扩展。更多还原

【Abstract】 The wear resistance of sintered, cast hypereutectic high chromium cast iron and TM52 steel bonded carbide under different impact energy conditions were compared. The development of the wear surface and the micro-crack of the sub-surface were analyzed by scanning electron microscopy（SEM）. The wear mechanism was also discussed. The results show that the high chromium cast iron prepared by liquid phase sintering has excellent impact abrasive wear resistance. Under the medium and low impact energy conditions, the wear resistance of sintered high chromium cast iron is significantly better than that of TM52（4 to 10 times）.Under the medium and high impact work conditions, the wear resistance increases more than 10 times compared to that of casting high chromium cast iron. The wear mechanism of sintered high chromium cast iron is mainly micro-cutting, as well as fatigue wear and brittle fragmentation under the high-energy impact work. The short rod-like M₇C₃-type carbides in sintered high chromium cast iron yield small split and stress concentration on metal matrix, while the martensite-based matrix with high strength and toughness, can effectively support and maintain a uniform dispersion of carbides and block micro-cracks initiation and expansion.更多还原