Preparation and wear properties of discontinuous ceramic fibre reinforced iron alloy by low isostatic press sintering

Abstract

Low isostatic press sintering (LIPS) behaviour was examined using a mixture of high speed steel powder and discontinuous alumina fibre, and mechanical properties of the obtained LIPS compact were estimated. LIPS is applicable to the composite system in which a reaction gas is generated during sintering because evacuation is continuously carried out during sintering. As the volume fraction of discontinuous alumina fibres is large, pores are formed in the fibre aggregated region, resulting in an increase in porosity. For discontinuous alumina fibre uniformly dispersed composite with no fibre aggregated region, the critical volume fraction of discontinuous alumina fibres exists and depends on both the ratio of the particle diameter of the high speed steel powder to the diameter of the discontinuous alumina fibre and the dispersion morphology of discontinuous alumina fibres. The dispersion of 20 vol.-% discontinuous alumina fibre in high speed steel leads to an increase in wear resistance.