Performance of titanium nitride-coated carbide-tipped circular saws when cutting stainless steel and mild steel

The use of TiN coatings on cutting tools for general ferrous machining applications to enhance tool life and increase productivity is now well established. However, application of coatings to the carbide-tipped cutting tools using the PVD process is a new activity. In this investigation a new experimental approach was used, in which TiN coatings were applied to carbide-tipped circular saw segments. The four cathode PVD technique was used for deposition at a low coating temperature. This results in a fine-grain, thin, hard film with excellent adherence to the substrate. When deposited on tools, coating acts as a chemical and thermal barrier between the tool and workpiece. Applications including machining mild steel and stainless steel benefit from the coating. Comparison between coated carbide-tipped circular saws and uncoated carbide-tipped circular saws is presented. The cutting test results have shown that TiN-coated carbide-tipped circular saws presented much better performance and longer tool life than the uncoated saws. This information will be useful in the development of a coating system applied to the carbide-tipped circular saw using PVD.