PERFORMANCE OF PVD-COATED CARBIDE TOOLS WHEN MACHINING TI-6AL-4V

This work investigates the performance of TiN and TiN/TiCN/TiN physica l vapor deposition (PVD)-coated carbide tools in continuous turning of Ti-6Al-4V. Significant improvement in tool life was achieved when mac hining Ti-6Al-4V with both PVD-coated tools under the optimum cutting conditions. Notching at the depth of cut (DOG) was suppressed and flan k wear, chipping and flaking of tool material on the rake face and/or at the nose of tools were the dominant failure modes. Tool life equati ons of the coated tools (when machining Ti-6Al-4V) were achieved by us ing a statistical regression analysis of the experimental data.