ANOTHER APPROACH OF SURFACE TEXTURE IN TURNING USING MOTIF AND ‘’Rk’’ PARAMETERS

The surface motif combination, ISO 12085:1996, is a method of analyzing surface texture alternatively to the central line system ‘M’. It gives a graphical evaluation of surface profile using mainly six parameters without filtering waviness from roughness. Another functional roughness characterization is introduced by the DIN 4776 and ISO 13565-2 standards through the ‘’Rk’’ parameters, which describe the shape of the relevant Abbott curves. This study presents the application of both the aforementioned methods in the analysis of turned textures carrying out turning tests for cutting conditions varied over a representative range. The workpiece material was a 304 stainless steel turned by a P30 cemented carbide tool. Close correlation was detected between many of the parameters considered and primarily feed and cutting speed, a fact that led to the development of regression models. Comparisons made to the variation of popular ‘’M’’ system parameters indicate that motif parameters provide an alternative way for controlling the turning process and determining optimal cutting conditions .