This paper deals with the search for an appropriate diamond cutting material and suitable tool geometry for CNC machining for processing the aluminium alloys AA2007 and AA7075 as well as the copper alloys bronze CuSn11Pb2 and brass CuZn39Pb3. The task also implies the optimisation of the process parameters for turning and milling using those new cutting tools particularly with regard to work piece quality and cost-effectiveness. As a part of this research this was accomplished by a series of cutting experiments and the subsequent material performance analysis. The practical tests with PCD- and CVD-tools have shown that an increasing feed is beneficial for the produced chip shape and at the same time strongly increases the surface roughness. Decreasing the depth of cut hardly showed any distinct impact on the surface quality, but resulted in longer chips and the tendency of developing a built-up edge.