: Coating methods in the science of metallurgy is used for coating on the tools surfaces. The resulting coating keeps the surface intact against destructive factors such as corrosion, wear, erosion and etc. Physical vapor deposition or PVD includes of vacuum deposition techniques and it is a general term to describe any of several ways of condensing vapor deposition to form the thin film on the surface of a substrate in a vacuum. Todays, hard coatings have a wide range of applications amongst which TiAlN and AlTiN are common examples; TiAlN coatings are preferred for cutting tools and machining and AlTiN coatings are appropriate for applications in aerospace. TiAlN coatings include thin film coatings are typically coated on the cutting and machining tools by PVD method. Coatings are obtained by an electron beam physical vapor deposition that to create coatings the powder target has been used. Powder targets are available at lower price, also less equipment is needed to produce them, so various attempts have been made to produce and optimize this target. Among the characteristics of this coating, it’s higher hardness and adhesion properties of this coating can be mentioned. To strengthen some of characteristics of these coatings a forth element can be added to them so that some improvements to the properties of resulting coating would be provided. Elements such as chromium which have the same atomic radius as Al do not create a substantial deviation in the coate lattice parameters. By adding chromium to coatings, less hardness (and probably more roughness) and very good adhesion to the substrates is observed. The roughness of the coatings increased with increasing chromium levels. Hardness is decreased by adding chrome in TiAlN coatings and with changes in the amount of chromium, hardness is not subjected to wide changes. Also adding chromium to coating increases elastic modulus. Fractures and crack initiation load is the tin and the amount in the TiAlCrN is much higher and it increases well by adding more chromium content. B y using a powder target, the amount of coating time has been reduced greatly (6 times) and it also will cause a sharp reduction in the cost of the coating process. The present project is aimed at improving and optimizing the properties of TiAlN coatings and studying the added chromium amount and its relationship with the type and amount of coating optimization. Benefiting from such data, this research is up to determine the required amount of chromium for TiAlN coating due to expected tool type, applications, and properties. Keywords PVD , Coating TiAlN, wear, alloying elements.
