Al 2O 3, TiC 0.7N 0.3 single-layered, and TiC 0.7N 0.3/Al 2O 3 duplex coatings were deposited on self-made Si 3N 4 and SiAlON substrates by chemical vapor deposition (CVD) technology, and their continuous dry turning of gray cast iron was carried out. Besides the measurement of adhesion force between coating and substrate, adhesion energies as one of the most important prerequisites were calculated. Si 3N 4-TiC 0.7N 0.3 and SiAlON-Al 2O 3 exhibited the highest value of 1010.9 N/m and 1021.4 N/m, respectively. The cutting life of Si 3N 4-TiC 0.7N 0.3/Al 2O 3 and SiAlON-Al 2O 3 are 8.7 times and 5.6 times of those uncoated substrates ( V c=200 m/min), respectively, whose adhesive strength satisfies the high-speed cutting conditions ( V c=300 m/min). This combines the benefit of both TiC 0.7N 0.3 and Al 2O 3 coatings, whose main wear mode is oxidative chemical wear of Ti and Fe. SiAlON-TiC 0.7N 0.3 and SiAlON-TiC 0.7N 0.3/Al 2O 3 have shorter cutting life due to their low adhesion energy and coating peeling. Adhesive wear is the main wear mode in the SiAlON-Al 2O 3 cutting process.