制备了一种新型的碳化物颗粒增强铁基粉末冶金材料，采用光学显微镜、扫描电镜、能谱分析仪和力学性能试验机等研究了烧结温度和退火温度对其组织与性能的影响。结果表明：随着烧结温度升高，碳化物形貌从块状向针状转变；l270℃烧结时的相对密度和硬度最高，1240℃烧结时的抗弯强度和冲击韧度最高；脆性针状碳化物在晶界上以半连续网状析出，降低了材料的性能；1200℃退火后，晶界上的针状碳化物分解并球化，其相对密度、硬度、抗弯强度和冲击韧度分别达到96．29／6，44．5HRC，628MPa，3．8J·cm^-2。%A new carbide particles reinforced Fe-based powder metallurgy material was prepared. The effect of the sintering temperature and annealing temperature on the microstructure and properties of the material was studied by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and mechanical property testing. The results show that the morphology of carbides changed from bulk to needledike with the increase of the sintering temperature. The relative density and hardness of the material sintered at 1 270 ℃ and the bending strength and impact toughness of the material sintered at 1 240 ℃ were maximal, respectively. The brittle needle-like carbides precipitated in semi-continuous network form along grain boundaries and thus decreased the property of the material. After annealing at 1 200 ℃, the needle-like carbides decomposed and spherified, and the relative density, hardness, bending strength and impact toughness of the material were 96. 2%, 44. 5 HRC, 628 MPa,3.8 J · cm^-2, respectively.
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