Surface finish parameters as diagnostics of tool wear in face milling

We describe a systematic series of wear tests in which surface profiles were measured at intervals during face milling of En24 steel, an aluminium alloy and a stainless steel. Profiles were measured by a stylus instrument and, in the case of the aluminium alloy, by a novel optical fibre instrument mounted on the machine headstock. Spatial frequency analyses are presented that show the long wavelength amplitude increases with insert wear, with a similar tendency in the high spatial frequencies (above the feed per tooth). Variation in tool set affected insert wear rate and the evolution of surface profile. Insert chipping damage was seen to increase the low spatial frequency content. The R_a parameter correlated with insert wear only for single point cutting. © 1997 Elsevier Science S.A. All rights reserved.