| According to thermodynamic and kinetic result, the requirement of thermodynamics and kinetics for the formation of VC particles were studied. The microstructure and three-dimensional appearance were studied by XRD, SEM, EDX and TEM. The effect of heat treatment on the structure and mechanical properties of composite was also studied. The corrosion and wearing resistance of composite compared with the matrix materials and the best heat treatment technology was determined.According to thermodynamics result, the reaction mole enthalpy has smaller effect on the formation of VC. The Gibbs free energy is the main factor. Cr7C3 has the lowest Gibbs free energy in Fe-Cr-Ni-V-C smelting alloy system. It forms easily when the temperature is low, which restricts the formation of others. The Gibbs free energy of VC is the lowest by higher temperature. When the temperature surpasses 1938K, Cr7C3 starts to decompose. VC particle forms rapidly at the same time.The reaction rate under different temperature and activation energy was got by kinetic result. The former will get down with the elevation of react-temperature. It also indicates that the formation of VC is ninety percent in one minute by 1727°C.XRD analysis shows that the matrix is formed by two-mixed phase of ferrite and austenite. V exists in V4C3 combining with C. Cr exists partly in Cr7C3. The TEM analysis of microstructure indicates that the reinforced particle is V4C3. Its electron diffraction pattern in the [011] direction is determined. SEM photography with deep corrosion proves that VC is spherical in space. Diameter analyzing of VC particles shows that it contains by 9.487% and its diameter scope is 5-10μm with the average of 6.647μm. The amount of carbon in matrix is 5.46% while the formation is 80.74%. VC particles have no change under heat-treatment. The impact toughness has a remarkable raise (ak=15.3 J/cm2) but the hardness is no change by quenched with no martensite, the former will rise but the latter will reduce with the prolongation of quenched-time. The matrix changes fromγ-Fe to P after high annealing, which raise the hardness and impact toughness slightly (HRC 35.3,11.3 J/cm2) with the dispersion of chromium-carbide.The wearing resistance increases after high annealing dues to the improvement of matrix microstructure. Abrasion test in wet paste solution shows that VCp/Fe composite especially after high annealing has the best wearing resistance under interaction of corrosion and abrasion. the ultimate heat-treatment technology is that heat preservation is in 950-980°C by 2h then cooling with furnace.
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