Titanium-aluminium-nitride (Ti1-xAlxN) coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6wt%Co inserts at 4 50℃. The tribological behavior was analyzed by sliding against steel and WC- 6wt%Co balls, while the turning performance was evaluated by a conventional tu rning machine at high cutting speeds without using coolants. In the tribological tests, the formation of transfer layer and the variations of hardness of the co atings played an important role for sliding against steel balls. For the coating s sliding against WC-6wt%Co balls, the Ti-Al-N coatings showed a similar frictio n coefficient, but the TiN coating exhibited a lower value. The difference could be explained by the tri-oxidation wear mechanism. In the turning tests, a super ior cutting performance of the coating was found at x=0.45, which endured 38 min utes before the tool flank wear reached the maximum value of 0.3mm, whereas only 20 minutes were endured for the TiN coating. The excellent performance of the c oatings in the turning tests could be explained by the enhanced mechanical prope rties and oxidation/diffusion resistance of the coatings. Titanium-aluminum-nitride (Ti1-xAlxN) coatings were deposited by close-field un balanced magnetron sputtering on M42 steel substrates and WC-6 wt% Co inserts at 4 50 ° C. The tribological behavior was analyzed by sliding against steel and WC- 6wt % Co balls, while the turning performance was evaluated by a conventional tuning machine at high cutting speeds without using coolants. In the tribological tests, the formation of transfer layer and the variations of hardness of the co atings played an important role for sliding against The balls could be explained by the tri-oxidation wear of steel, the Ti-Al-N coatings showed a lower value. In the turning tests, a super ior cutting performance of the coating was found at x = 0.45, which endured 38 min utes before the tool flank wear reached the maximum value of 0.3mm, and only only 20 minutes were endured for the Ti N coating. The excellent performance of the c oatings in the turning tests could be explained by the enhanced mechanical properties and oxidation / diffusion resistance of the coatings.