Microstructure and Properties of A New-Typed Carbide Particles Reinforced Fe-Based Powder Metallurgy Material

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 needle-like 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.