| The fabrication of Fe-WC surface composite by using reactive cast-infiltration has been studied for the first time. The WC in the composite was produced from combustion reaction W+C=WC, in which (Al+CuO) was used as combustion-supporting reagent. The casting material was gray cast iron. The effect of various processing parameters , including the content of combustion-supporting reagent, the density of pressed compact, the pouring temperature and the vacuum, on the formation of cast-infiltration was experimented. The result of the experiments showed that when the content of combustion-supporting reagent was at the range of 5%~10%, the density of raw briquette was about 30%, the pouring temperature was at the range of 1450℃~1550℃ and the vacuum was about 0.04MPa, the Fe-WC surface composite can be produced on the gray cast iron .The composite was analyzed by using modern materials analysis instrument, including X-Ray Diffraction (XRD), Scanning Electron microscope(SEM), Energy Dispersive X-Ray (EDX) and Metallography Image Analysis system etc. The result showed that the structure of the cast-infiltration layer were WC and bainitic matrix mainly, and including small quantity of FesWaC. The total volume percent of WC was about 30% in the cast-infiltration layer. An excellent metallurgical combination existed between the cast-infiltration layer and casting material.The hardness and wear resistance of Fe-WC surface composite was tested. It was proved that the hardness of the cast-infiltration layer was about HV850, and the abrasive resistance was 99 times that of the 45Mn2 iron and 15 times that of the high chromium cast iron.The kinetic process of the reactive cast-infiltration was analyzed, and a kinetic model of the reactive cast-infiltration process was presented. It was believed that the reactive cast-infiltration process was co-action of combustion synthesis, liquid iron infiltration and the dissolution of compact and its reactant.
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