Abstract: | High speed milling experiments with cutting speeds of up to 7000 m/min have been performed on an aluminium alloy (AlZnMgCu1.5, AA 7075) and a steel (40CrMnMo7). Both materials were heat treated to produce a variety of microstructures in order to investigate the influence of microstructure on segmentation during chip formation. In case of the aluminium alloy it has been shown that chip formation is governed by the precipitation state, but not by the hardness of the material. In contrast, hardness can be used for a qualitative prediction of chip shape of the steel. In all cases, the chip formation mechanisms remain essentially unaffected by cutting speed, i.e. no transition from continuous to segmented chips occurred. |