Friction and wear behavior of surface nanocrystallized aluminium alloy under dry sliding condition

One way of improving the surface properties of engineering material is by reducing the grain size at the surface. Controlled ball impact process is developed for producing surface nanocrystallization and improves the surface mechanical properties by inducing compressive residual stress on the metallic materials. Improvement in the surface mechanical properties will affect the tribological properties. This paper reports the influence of the surface nanocrystallization on the tribological properties of aluminium alloy. Tribological properties were evaluated under dry sliding conditions using a reciprocating wear test facility. The friction coefficient of the treated surface is lower than that of the untreated samples and treatment improves the wear resistance of aluminium alloys. The improvement in the friction and wear properties is due to enhancement of surface strength, due to grain refinement and induction of compressive residual stress. The worn surfaces observed using scanning electron microscope reveal the dominant adhesive nature of wear and mild abrasive wear.