系统对比研究了粗晶粒TM52钢结硬质合金与分别采用真空烧结和低压烧结制备的细晶粒TM52钢结硬质合金在不同冲击功工况下的抗磨料磨损性能与行为,并在对磨损面形貌进行电镜观察分析的基础上探讨了粗晶粒TM52钢结硬质合金的磨损机理。研究发现,粗晶TM52合金的抗磨料磨损性能随着冲击功的逐步提高呈现先下降后增强的变化规律,这与其高锰钢基体在高冲击功条件下的高硬化速率及硬化效果更快、更充分有关。相对于细晶粒钢结硬质合金,粗晶粒TM52钢结硬质合金在抗冲击磨料磨损方面具有明显的性能优势,尤其在高冲击功(3~4J/cm~2)条件下,耐磨性能可提高40%~80%。在此工况下磨损机制主要为碾碎性磨料磨损、擦伤式磨料磨损和疲劳磨损,凿削式磨料磨损不明显。
The impact abrasive wear resistance of coarse grained TM52 steel bonded carbide was systematically evaluated. And it was compared with the normal fine grained TM52 which were sintered in vacuum and at low pressure (about 5 MPa) under diffe- rent impact energy working conditioru Then the wear mechanism of coarse grain TM52 was investigated based on the electron micros- copy inspection analysis of its wear surface. The results revealed that the impact abrasive wear resistance of the coarse grained TM52 steel bonded carbide decreased first and increased later with the gradual improvement of the impact load, which was closely related to the high hardening rate and hardening effect of high manganese steel matrix under high impact energy conditions. The impact abrasive wear resistance of coarse grained TM52 steel bonded carbide had obvious advantages compared with fine grained TM52, especially under the high impact energy (3-4 J/cm2 ), the wear-resisting performance increased by 40%-80%. Its wear mechanism mainly in- cludes grinding abrasion, scratch abrasion and fatigue abrasion, while chisel cutting abrasion was not obvious.