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In the present work, AlSi9Cu3Mg alloy matrix composites reinforced with 15 and 19% (vol.) B 4 C p were produced by squeeze casting route at 850 °C under low vacuum. Titaniumcontaining flux (K 2 TiF 6) was used to promote the wetting between B 4 C and liquid aluminium metal. It was found, from the microstructural observations, that the wetting improved by the formation of a thin Ti-rich reaction layer. In order to investigate the wear properties, the samples were subjected to reciprocating wear tests against AISI 4140 pin under dry sliding conditions. Effect of B 4 C volume fraction, sliding velocity, applied load and sliding distance on reciprocal dry wear behaviour of composites was studied using general full factorial experimental design. Effects of factors and interactions on the coefficient of friction (COF) and the wear rate values of both composite specimens and counter materials were studied. Worn surfaces and wear debris were characterised using field emission gun scanning electron microscope (FEG-SEM), Energy Dispersive X-Ray Spectroscopy (EDS), optical microscope (OM) and X-Ray diffraction (XRD). From microstructural investigations, wear mechanism suggested as a combination of adhesive, abrasive, and delamination wear.

In the present work, Al-B4C composites were produced by casting route at 850°C and titanium-containing flux was used to overcome the wetting problem between B4C and liquid aluminium metal. The microstructure of matrix/reinforcement interface was investigated using SEM studies with or without Ti added composites. The reaction layer was also characterized with EDS analysis and X-ray mapping. It was found from the microstructural observations by high resolution field emission gun SEM (FEG-SEM) that the wetting issue was effectively solved by the formation of very thin (80-180 nm in thickness) Ti-C and Ti-B reaction layers.