Effect of grain refinement on wear properties of Al and Al–7Si alloy

The effect of grain size of Al and dendritic arm spacing (DAS) of α-Al in Al–7Si alloy on wear behaviour of Al and Al–7Si alloy were investigated in the present study. The results show that the wear rate decreases with the decrease in the grain size and DAS of Al and Al–7Si alloy, respectively, at a load of 50 N, sliding distance of 1800 m and sliding velocity of 1 m s−1 under dry sliding condition. Al–7Si alloy was grain refined using various grain refiners such as Al–1Ti–3B, Al–3Ti and Al–3B while Al was grain refined with Al–5Ti–1B. The results suggest that the wear properties are not dependent on the type of grain refiner used, but depend on the grain size/DAS of the metal/alloy and the presence of second phase (eutectic Si in Al–Si alloy). Effect of fading of grain refiner on wear rate was also clearly observed.