COATED SUBSTRATES AND METHODS OF MAKING SAME

摘要

Coated substrates having high wear resistant coatings are disclosed. The coatings include at least one layer of either titanium oxycarbonitride or titanium aluminum oxycarbonitride, such that the layer has an oxygen to titanium atomic percent ratio in the range of about 0.01 to about 0.09 and an aluminum to titanium atomic percent ratio in the range of about 0 to about 0.1. The coatings have a hardness to Young's modulus ratio of at least 0.06. The substrate may be a cutting insert. Methods of making such coated substrates are also disclosed in which layers comprising titanium oxycarbonitride or titanium aluminum oxycarbonitride are deposited by medium temperature chemical vapor deposition (MT-CVD) on substrates in the temperature range of about 750 to about 950 °C using a mixture of gases wherein the ratio of the hydrogen gas to the nitrogen gas is greater than 5.