Microstructure, Hardness, Wear Behaviours of A356/Fly Ash Composites Fabricated by Powder Metallurgy Method

In this study, we investigated the microstructure and wear behaviour of A356/fly ash composites fabricated using the powder metallurgy method. Fly ash was added to A356 Al alloy in four different ratios by weight and mechanically milled for 1 h. The milled composite powders were pre-formed under 800 MPa pressure and sintered for 1 h under vacuum at 590 °C. The microstructures of the produced samples were examined by optical microscope, SEM, EDS and XRD. The hardness measurements and wear tests were performed to determine the effect of fly ash content on the properties of the samples. As a result of the study, it was found that the hardness value increased with the increasing fly ash amount up to 2 wt% and decreased after 2 wt%. The wear test results were consistent with the hardness results. The maximum weight loss occurred in the composite containing 4 wt% fly ash.