Effects of machining abuse on the surface properties of AISI 316L stainless steel

A Design of Experiments (DoE) approach was used to characterise the effects of dry machining at abusive conditions on the austenitic stainless steel AISI 316L. Surface roughness, hardness, martensite fraction, residual stresses and surface defects (welded chips, cracks) were evaluated against the cutting parameters (speed, depth-of-cut and feed) to build a model weighting their contribution. Results are presented in colour contour plots which allow for an in-depth understanding of the parameters' combined effects on the surface properties of the material upon dry milling. Using the statistical model it was possible to identify optimum combinations of cutting parameters on the grounds of minimising undesirable effects on the material. Eventually, a sample “risk of failure” map was derived by evaluating the impact of the process parameters' statistical variations.