Thermal and tribological characterizations of millscale-particles-reinforced ceramic matrix composites

Abstract

This paper evaluates some basic functional properties of iron-millscale-reinforced ceramic matrix composites (CMCs) as potential material for automobiles and aircraft brake pads’ application. The particulate CMCs were produced by the powder metallurgy method. Iron millscale particles’ addition varied from 3 to 18 wt.% in a matrix comprising a mixture of silica, magnesia and bentonite. After sintering, the composites were subjected to coefficient of friction (COF), wear, thermal and microstructural characterizations. Microstructure of the composites showed a uniform distribution of millscale particles in the ceramic matrix with a strong interfacial bonding between the particles. The composites demonstrated a comparatively high resistance to wear, appreciable COF (0.506–0.561) and a modest thermal conductivity (0.39–0.53 W/m K) coupled with high thermal stability. Contributions to these superlative performances were provided by the high level of friction induced on composites’ surfaces and strong interfacial bonding developed during sintering.

Keywords

• Ceramic matrix composites
• wear
• thermal stability
• microstructure