Circular saws coated by TiN (titanium-nitride) reach very high surface microhardness which enables their using for separation of material of high mechanical tenacity. It is very suitable for cutting medium- alloyed and hard steel. The coat characteristics enable to heighten circumferential speed and feed rate nearly by 50 % and it very shortens the time of working cycles. This coating with a titanium base 3 microns thick obtained at a process temperature of approximately 490°C. It guarantees an oxidation temperature of 520°C. Its low thermal conductivity provides a reliable heat shield for the sublayer. Materials: PVD coating suitable for cutting low alloy steel and must always be used with plenty of lubrication. It is not suitable for cutting copper, brass or bronze.