Wear characteristics of recycled cast Al-6Si-3Cu alloys

Recycling of Al-Si alloys for high integrity structural components for the automotive industry applications has gained attention in the recent times. In this article, scrap of cylinder heads containing 6.01%Si and 2.62%Cu were recycled by casting into four alloys invariants: base alloy (no alloying elements added), 0.02%Ca, 0.38%Fe and 0.9%Fe+0.45%Mn additions. The structural properties were analysed through optical and SEM/EDS microscopy, X-ray diffraction (XRD). The wear characteristics of the alloys were investigated using a multi-pass ball on the flat reciprocating method under a normal load of 30 N and velocity of 4 mm/s. The results showed delamination and adhesive wear as the predominant wear mechanisms for the recycled Al-Si alloys. The base and 0.02%Ca alloys exhibited the lowest coefficients of friction and rates of wear. A comparison of the wear data to the published data on primary alloys revealed that our secondary alloys have the potential for applications in the automotive industry.