Effect of New Superhard Phases Formation on Properties of Composite Processed by SHS
A composite was produced from initial powder mixture of B4C (70 wt.%) and Al (30 wt. %) with WC-Co additives introduced during ball-milling and acting as catalysts by self-propagating high-temperature synthesis and followed by heat treatment of raw samples under gaseous nitrogen flow at 650, 800, 1000, 1150 and 1450 °C, respectively. Formation of different new superhard phases was detected via XRD investigation and analysis of microstructures. Micromechanical properties were tested by nanoindentation. The tribological behavior in dry sliding conditions of the composite was investigated using the ball-on-disk technique against alumina balls. The friction coefficient of the composite increased and wear rate decreased with formation of c-BC2N, c-BN, B13C2, W2B5, Al3BC, AlN, etc. contents during heat treatment at increased temperatures.
Prof. Irina Hussainova
L. Kommel et al., "Effect of New Superhard Phases Formation on Properties of Composite Processed by SHS", Key Engineering Materials, Vol. 527, pp. 137-142, 2013