TiAlN, CrN, TiAlCrN is a new hard coating material developed in recent years. TiAlN coated blades have been commercialized. Its chemical stability and oxidation wear resistance, with its high alloy steel, stainless steel, titanium and nickel alloy tool life than TiN coating 3 to 4 times higher. In addition, TiAlN coating with a suitable aluminum concentration, when cutting tool rake and chip interface will produce a layer of hard inert protective film, the film has better thermal insulation can be more effective For high-speed cutting. For example, the Kennametal H7 blade is TiAlN-coated and is designed for high-speed milling of high-performance materials such as alloy steel, high-alloy steel and stainless steel. CrN is a titanium-free coating suitable for cutting titanium and titanium alloys, copper, aluminum and other soft materials with good chemical stability and no stickiness. TiAlCrN is a gradient structure coating, not only has high toughness and hardness, but also a small friction coefficient, suitable for milling cutter, hob, tap and other tools, cutting performance was significantly better than TiN.