The frictional sliding behaviour of cast Al-Si alloy was investigated with and without DOT 4 hydraulic brake fluid lubrication/environments.Cast Al-Si specimen was produced from wrought alloy and the specimen surface was metallurgically prepared.The as-cast product was characterized with aid of micro-hardness tester,the chemical composition was analysed by X-ray fluorescence (XRF),while X-ray diffraction (XRD) was used to identify phases present,microstructures and surface examinations were done on a high resolution metallurgical Optical Microscope.The properties of the polished and worn sample surfaces were examined by Scanning electron microscope (SEM) equipped with Energy dispersive X-ray (EDS) facilities.A 6mm diameter alumina ball under varying normal loads (3-10 N) was rubbed against the surface of the cast Al-Si coupon specimen.The dry and wet sliding wear behaviour was assessed based on the CoF-sliding time behaviour.From the results,the average CoF values of 0.9064 for dry and 0.2038 for wet contacts were obtained.Comparatively,1.03E-06 and 4.21 E-07 minimum wear intensities;and 467290 and 132170 wear resistances were obtained for dry and wet contacts respectively.Behaviour of cast Al-Si in DOT4 were compared with its performance in DOT3 regarding the hydraulic brake system application.
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