Enhanced tool wear characteristics of carbide tool inserts having a novel surface structure

摘要

This paper presents the result of an investigation into the cutting characteristics ofelectrical discharge machined (EDMed) surface-modified carbide cutting tool inserts. The tool insertswere coated with Titanium Nitride (TiN) by physical vapour deposition (PVD) method. In this study,comparative cutting tests using TiN coated control specimens with no EDM surface structures andTiN coated EDMed tools with a crater-like surface topography were carried out on mild steel. Variouscutting speeds, up to an increase of 40% of the tool manufacturer‘s recommended speed wereinvestigated. Thirty cuts (passes) were carried out for each inserts at the speeds investigated. Afterevery five cuts (passes), microscopic pictures of the tool wear profiles were taken in order to monitorthe progressive wear on the rake face and, on the flank of the insert. The power load was monitoredfor each cut using an on board meter on the machine. Results obtained confirmed advantages ofcutting at all speeds investigated using EDMed coated inserts in terms of reduced tool wear.Moreover, the surface finish on the work-piece was consistently better for the EDMed inserts. It istherefore concluded, that TiN coated EDMed crater-like surface structure on tool inserts canconsiderably improve the tool performance.