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The wear behavior of SiC bonded diamond materials produced by liquid silicon infiltration in diamond preforms was investigated. The wear behavior in sand blasting tests (SiC abrasives, 5 bar pressure) was correlated with the microstructure. All SiC bonded diamond materials showed a wear, which was approximately 10 times less than the wear behavior of the reference SiC material.Systematic changed microstructures were created by increasing the infiltration temperature. As the infiltration temperature increases, a graphite layer is formed at the diamond-SiC interface. At the highest infiltration temperature (1670 °C), the layer thickness reaches approx. 580 nm. The results show that wear resistance is not negatively affected by the graphite layer. On the contrary, for materials with a graphite layer thickness of up to 70 nm, the wear resistance increases by up to 30 %. The wear increases again only at the highest infiltration temperature. However, this is probably caused more by the internal damage to the diamonds and not by the graphite layer at the interface.

Materials with high thermal conductivity are required in a wide range of thermal management applications. Silicon carbide (SiC) bonded diamond materials, which can be produced without pressure, are a possible candidate for such applications. They exhibit thermal conductivities >650 W/(m·K) depending on the diamond content, diamond grain size and residual silicon content. It is difficult to experimentally determine the influence of these factors on the thermal conductivity separately, as changing one of these parameters affects the other parameters. Therefore, a method for generating digital microstructures of SiC- bonded diamond materials was developed and the thermal conductivity was calculated as a function of the grain size These data were compared with real structures.