Dry sliding wear and surface morphological examination of an aluminium matrix composite reinforced with palm kernel shell

Abstract

The wear resistance and microstructural features of aluminium AA6063 based composites reinforced with seven different mass fractions of palm kernel shell (PKS) particles (0, 2.5, 5, 7.5, 10, 12.5 & 15wt%) fabricated by stir-casting, were characterized using pin-on-disk tribometer, optical microscope and image analysis. Image analysis revealed both the particle size and shape descriptors for the composites microstructural features. The average grain sizes of all the composites were higher than that of the unreinforced AA6063 matrix. Wear test conducted under dry sliding condition show that the volume reduction and specific wear rate increased to a maximum at 5wt% PKS addition and then decreased to the lowest level at 10wt% PKS. Subsequent addition of PKS above 10wt% yielded a further increase in the composites volume loss and specific wear rate. Composite sample reinforced with 10wt% PKS exhibited wear resistance response better than that of the unreinforced alloy. Image analysis afforded a comprehensive understanding of the microstructural features of the composites which influenced their behaviours.