Aluminium alloy reinforced with fly ash: Techniques and particle size

Utilization of metal matrix composite materials has grown very fast rate owing to its high weight ratio, low density and low coefficient of thermal expansion. High-temperature resistance, as well as low maintenance, is also an added advantage of using this composites. Fly ash which has low ash density is mainly used as a reinforcement in molten metal, normally reduces overall weight as well as the density of the fabricated composites. Fly ash particles are mainly preferred because of their good mechanical properties and low cost. Ex-Situ methods are mostly solid state processing and liquid state processing. Solid state which includes Powder Metallurgy (PM). Liquid state processing includes Stir Casting, Squeeze Casting, Compo Casting, and liquid metallurgy. In the recent past, several researchers have utilized the above said conventional methods to prepare the composites. Comparatively, powder metallurgy for solid state and stir casting for liquid state processing are highly preferred methods. This paper provides a review of the comprehensive literature on the fabrication techniques, the overall performance of variation in fly ash size and weight percent in the preparation of the fly ash-reinforced aluminium alloy composites. Also its corresponding tribological properties such as wear rate and friction coefficient with respect to variation in the content of fly ash are also reported.