Abstract
The influence of coating thickness on the life time of titanium nitride (TiN) PVD coated high speed steel (HSS) cutting tools has been studied using planing and turning as machining test methods. The thickness of the coating was found to have a significant effect on tool life. In the planing tests a coating thickness of 2-3 μm was found to give the longest tool life. In the turning tests the tool life increased as the coating thickness increased, up to the maximum 6.0 μm thickness tested. The chemical composition of the cutting fluid was also found to affect the tool life. The life of the coated tools was shorter in planing tests when using cutting fluids which contained EP (extreme pressure) -additives, sulfur additives showing shorter life than chloride.additives.