INFLUENCE OF THE REINFORCEMENT PHASE COMPOSITION ON THE STRUCTURE AND ABRASIVE WEAR RESISTANCE OF ALUMINUM MATRIX COMPOSITES REINFORCED WITH B4C AND SIC

Abstract

Aluminum matrix composites reinforced with ceramic particles are widely used in parts and components operating under sever friction and wear in the presence of abrasive particles. This work investigates the effect of the dispersion and the amount of B4C and SiC reinforcements ranging from 0 to 25 wt % in the initial powder mixture on the microstructure, micromechanical properties, and abrasive wear resistance of aluminum matrix composites. It is shown that B4C and SiC reinforcement particles contribute to the refinement of the aluminum matrix. Micromechanical properties determined by instrumented microindentation indicate that the hardness of the composites exceeds the hardness of sintered aluminum, and Al-25% SiC composite has the highest mechanical load resistance compared to other composites studied. Pin-on-plate wear tests of samples sliding against fixed electrocorundum grains revealed the greatest abrasive wear resistance of Al-25% SiC and Al-12.5% В4С-12.5% SiC composites, and the minimum resistance was observed for Al-25% B4C. These materials demonstrate adhesive and abrasive wear behavior with the formation of characteristic wear grooves and peeling pits.