Investigation of microstructure, mechanical and wear behaviour of B4C particulate reinforced AZ91 matrix composites by powder metallurgy

351-354In this study, AZ91 and AZ91 matrix composites reinforced with three weight fractions (10, 20 and 30 wt. %) of B4C particulates have been produced by powder metallurgy using hot pressing. Microstructure, hardness, density and mechanical properties of the samples are investigated. Microstructure characterization revealed the uniform distribution of particulatesin matrix. The presence of Mg, Mg17Al12 and B4C are verified by SEM and XRD. Wear tests are performed under loads of 5, 10, 20 and 30 N. Wear tests show that wear performance of the composites is improved with increasing particulate content. Observed wear mechanisms are oxidative and abrasive. The addition of B4C particulates led to significant increase in hardness, 0.2% compressive yield strength, ultimate compressive strength and failure strain