Material behaviour of aluminium 7075 and AISI 1045 steel in high speed machining

In high speed machining, material behaviour is characterized by high deformation and strain rates with occuring high gradients of temperature and deformation leading to a change in the process of chip formation compared with conventional cutting. Due to the short time contact between tool and workpiece at high cutting speeds and multiple single cutting edge engagements, e.g. in milling, the process of chip formation during one engagement is difficult to analyze. To determine the occurences during chip formation, model experiments with single cutting edge engagements not influenced by successing engagements are conducted. The effects on workpiece surface and on machined material depending on cutting parameters and workpiece material, are analysed. Results of the model experiment can be used in process design to determine optimum cutting conditions in machining at high cutting speeds.