SAE International Effect of B 4 C Particles on Dry Sliding Wear Behavior of LM-13 Metal Matrix Composite 2013-01-1174

LM-13 aluminum alloys reinforced with B\u2084C particles (5, 10, 15 wt. %) were prepared by gravity die casting. The samples were characterized on the basis of microstructure, microhardness, XRD and SEM. The microhardness tests indicated increased hardness values of the metal matrix composite (MMC) as B\u2084C percentage increased. Optical microscopic observation revealed presence of rhomboidal hard B\u2084C particles distributed randomly in the LM-13 matrix. Presence of B\u2084C was also confirmed with XRD Analysis. The dry sliding wear behavior of this LM-13 - B\u2084C composite was investigated by means of the pin-on-disc technique. The results showed that as the B\u2084C % increased, the volumetric wear decreased proportionately - indicating the active role of the B\u2084C particles in wear reduction. Study of the worn surfaces of the composite using the SEM suggests presence of adhesive and abrasive wear mechanisms with evidence of transfer films. The improvement in wear resistance points to the presence of hard B\u2084C particles which acts as a positive reinforcement in the LM-13 matrix. The wear and hardness results suggest that the material could be a suitable candidate for brakes disc/drum application in light automotive vehicles.