Roughness Analysis of the Holes Drilled on Al / SiC Metal Matrix Composites Using Atomic Force Microscope

Abstract

Metal matrix composites (MMCs) possess significantly improved properties including high strength to wear ratio, high modulus, superior wear resistance and corrosion resistance compared to unreinforced alloys. In spite of the advantages, the Aluminium based metal matrix composites have not yet found a wide employment in the commercial applications, because the the matrix cause serious problems in machining / drilling, such as high drilling forces, tool wear, and poor surface finish due to the hard particles. The drilling of Al/SiC metal matrix composite has received a serious attention for many years. Different specimens were prepared from Aluminium / Silicon carbide (Sic) metal matrix composites by stir casting method by varying the weight percentage of Sic and the investigation has been carried out on the specimen by drilling holes on them. Surface finish is an important factor to be taken into account in the drilling process. So, it is more necessary to predict the average surface roughness of the materials. Then the roughness of the drilled holes made on the specimen was studied using Atomic force microscope. The investigation was carried out with their characteristics being studied by comparing various parameters such as cutting speed, feed rate and so on. The average roughness was studied on 30µm X 30µm and 15 µm X 15µm horizontal section and vertical section. Their histograms were also studied.