ABSTRACT
Iron aluminide intermetallics exhibit excellent oxidation and sulfidation resistance and are therefore considered as the matrix in metal matrix composites, or the binder in hard metals or cermets. In this paper we discuss the processing and properties of liquid-phase sintered iron aluminide-bonded ceramics. It is found that ceramics such as TiB2, ZrB2, TiC, and WC may all be liquid phase-sintered. Nearly complete densification is achieved for ceramic volume fractions ranging up to 60%. Depending on the composition, room temperature three point-bend strengths and fracture toughnesses reaching 1500 MPa and 30 MPa m1/2, respectively, have been found. Since the processing was carried out in a very simple manner, optimized processing is likely to result in further improvements.
