It is necessary to elucidate the relation between characteristics of work materials and cutting phenomena, in order to select a certain rational condition in cutting of aluminum alloys. In this study, an investigation on effects of characteristics of work materials on machinability was carried out by a simple model experiments. Various aluminum alloys were examined by sintered diamond tool and high speed steel SKH4A tool. The results may be summarized as follows: The cutting state is controlled by the built-up edge. In cutting without built-up edge, however, the mechanical properties of work material affect its cutting process, that is, the cutting forces are in proportion to hardness of work. The tangential force is strongly influenced by shear energy at chip formation. Cut surface roughness and depth of flow layer decrease with increase in hardness and decrease in elongation of work.
