Determination of the effect of graphene produced by cheap method on the performance of SiAlON based ceramic cutting tools

Thanks to superior properties, SiAlON ceramics are typically prefered to produce cutting tools which are used to cut and shape the hard materials especially used at aviation and automotive industry. However, due to the low thermal conductivity of SiAlON ceramics, high temperatures are reached and cause to occur micro faults and shorten the service life. This problem can be solved by adding graphene which has high thermal conductivity, to SiAlON ceramics as the secondary phase. However, graphenes obtained by current production methods are not suitable for industrial applications due to their high costs. The aim of this study is to determine the effects of graphene produced by cheap method on the properties of SiAlON ceramics and to investigate its suitability for ceramic cutting tool. SiAlON powders were added to the graphene dispersion which was produced by university-industry cooperation to obtain graphene-SiAlON compositions contain % 0.75, 1 and 1.25 by weight and they mixed with three different techniques. The obtained graphene-SiAlON compositions were sintered in the SPS furnace. Microstructure, hardness, fracture toughness and thermal diffusivity properties of the produced graphene-SiAlON composites were measured and compared. It was observed that the hardness and thermal conductivity values decreased depending on the amount of graphene, while the fracture toughness increased. In addition, material properties change depending on the mixing techniques used throughout the study, and this is explained by the distribution of graphene layers in the SiAlON matrix.