Possibly the first work of note on HSM was that of Salomon who ran a series of applied experiments from the period 1924 to 1931, when a German Patent was granted for this work. The Patent was founded upon a series of cutting speed curves plotted against machining temperatures for a range of materials (Fig. 214). In these tests Salomon achieved peripheral cutter speeds of 16,500 m min–1, utilising either fly-cutters – for chip morphology data, or helical milling cutters – notably when cutting aluminium. Salomon contended that the cutting temperature ‘peaked’ at a specific cutting.
