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The paper reports wear and friction performance of Al-12Si aluminum alloy reinforced with 1.5 wt% submicron boron carbide (B4C) particles. Composite material is fabricated by ultrasonic stir casting process. Microstructural examination is carried out using optical microscopy and field emission scanning electron microscopy (FESEM). Incorporation and agglomeration-free dispersion of B4C particles is detected in the aluminum matrix. Pin-on-disc tribotester is used to evaluate tribological performance of fabricated composite and base alloy under room temperature dry conditions. Nominal contact pressure of 0.707 MPa is applied against EN31 steel counterface, and sliding speeds are varied between 0.25 and 1.25 m/s. Influence of sliding distance is investigated by varying sliding durations from 10 to 40 min at two fixed load-speed (PV) factors of 10 and 25 Nm/s. Worn pin surfaces and collected wear debris are analyzed using FESEM and energy-dispersive spectroscopy to reveal undergoing wear mechanisms. After initial decrease, wear rate increased almost linearly with speed and became twofold at the top speed. Wear rate transition is seen at 0.5 m/s with sliding distance for the applied pressure. Friction coefficient is not influenced significantly with sliding distance for the fixed PV condition. Adhesion and delamination governed the wear mechanism of base alloy while mechanically mixed layer played key role in the wear performance of composite matrix. Improved wear resistance of aluminum matrix is observed due to incorporation of small amount of B4C particulates making the composite better suited for wear-resistant applications than base alloy. [ABSTRACT FROM AUTHOR]