Wear studies of tungsten carbide cutting tools using micro-beam techniques

Particle accelerator based mu-PIXE and mu-RBS techniques along with optical microscopy, SEM and EDS were employed to examine the worn faces of uncoate d tungsten carbide inserts used for cutting free machining steel. The study is concentrated on the deposited manganese sulfide onto the rake and flank faces of the tool tips, and on the changes in the tool matrix composition arising from the prevailing wear mechanisms. The manganese and iron distrib utions on the worn faces of the tool tips showed a very good reproducibilit y for similar cutting conditions. Evidence of the decomposition of tungsten carbide in the crater and the diffusion and/or oxidation of the freed tung sten is presented. The strength of the mu-PIXE and mu-RBS versus convention al techniques is demonstrated by the ability of the former techniques to re solve the structure and the composition of deposited layers in three dimens ions.