Plasma Sintering of Fe-NbC Composites

摘要

Ferrous alloys have been reinforced by particle dispersion using hard ceramics such as niobium carbide, tantalum carbide, or titanium carbide. The resulting composites have a number of potential applications in the ceramic and textile fields where abrasion plays an important role. Their cost-efficient production allows them to exceed the capabilities of conventional non-reinforced tool steels. The present study presents some of the results obtained sintering Fe-NbC composites either in a resistive oven or in a d.c. plasma furnace. Final densities of approximately 95% TD were obtained in the latter atmosphere at temperatures as low as 750℃. Dilatometric studies carried out in resistive furnace indicated that this composite did not show significant densification below 1240℃ in the presence of a liquid phase formed by the addition of small amounts of Fe_3P. The differences between conventional and plasma sintering are discussed herein along with the effect on the microstructure of the composite.