Study of Abrasive Wear and Abrasion Heating of Mg and Al Matrix Composites Reinforced with B4C and Cr

Abstract

This paper has focused on abrasive wear and abrasion heating of Mg- and Al-based B4C and Cr reinforced composites. The B4C and Cr have been added in 5% in the Mg- and Al-matrices and their composites have been fabricated by a squeezed stir casting method. The matrices and composites are evaluated and characterized for microstructure, hardness and X-ray diffraction. The abrasive wear and temperature rise during abrasive wear tests are carried out using a tribo-tester machine. The microstructure of Mg- and Al- matrices and their composites mainly show a uniform distribution of the B4C and Cr reinforcements. The hardness of the composites enhanced upto 72% by including B4C and 30 to 37% in the case of Cr composites in comparison to Mg- and Al- matrices. Temperature rise during abrasive is found more in the case of B4C reinforced composites in comparison to Cr amalgam composites and the abrasive resistance of B4C composite is high in comparison to Cr amalgam composites. The wear rate of boron carbide composites is approximately 2–6 times lower than the Mg matrix under different conditions. SEM image analysis mainly shows the cutting and ploughing material removal mechanism in abrasive wear.