Experimental investigations from conventional to high speed milling on a 304-L stainless steel

Last years analytical or finite element models of milling become more efficient and focus on more physical aspects, nevertheless the milling process is still experimentally unknown on a wide range of use. This paper propose to analyse with accuracy milling operations by investigating the cutting forces values, shape of cutting forces curves obtained for different cutting speeds, and related phenomena as tool wear or tool run-out. These detailed experimental data in milling constitute a suitable experimental basis available to develop predictive machining modelling. All the tests have been conducted on the 304L stainless steel in many cutting configurations and for different tool geometries. The machinability of the 304L stainless steel with different tools geometries and configurations in shoulder milling is defined by three working zones: a conventional zone permitting stable cutting (low cutting speed; under 200-250 m.min), a dead zone (unfavourable for cutting forces level and cutting stability; between 250 and 450 m.min), and a high speed machining zone (high cutting speed; up to 450-500 m.min). All the used criteria (cutting forces, chips, wear) confirm the existence of these different zones and a correlation is proposed with cutting perturbations as run-out, cutting instability, ploughing and abrasive wear.