Study on the Composition Graded Cemented Carbides/Steel Composite by Spark Plasma Sintering

Steel coated with high wear-resistant and high corrosion-resistant hard materials are widely used, but this composite product does not always obtain the properties which coating materials originally have, mainly because coating materials with enough hardness could not be jointed densely and thickly as desired. It is possible to realize the aimed properties on the coated product if the cemented carbide could be coated in dense and thick way. In order to do so, over-coming the thermal stress between the steel and the cemented carbides is necessary, because the stress may cause the cracking of the product and the peeling of the cemented carbides from the steel. Study indicated that the coating the powder of different Co percentage of cemented carbides in multiple layers on steel and using the Spark Plasma Sintering process to sinter and joint the steel and cemented carbide simultaneously solves the problem. The characteristics of this process are low-temperature and short-time sintering. Crack-and peel-free coated product was realized from this process.