Friction-wear behaviors of chemical vapor deposited diamond films at high temperaturesA diamond film was deposited on YT14 hard alloy cutting tool using a сhemical vapor deposition. The coefficients of friction and wear behaviors of the obtained diamond films at 500, 600, and 700 °C were investigated using a high temperature tribological tester. The results show that the C of diamond film is fully released at 700 °C, generating CO and CO 2 . The (220) plane of diamond film is oxidized fully at 500 °C, while the (110) plane of diamond film is oxidized at 700 °C. The average coefficients of friction of diamond film at 500, 600 and 700 °C are 0.55, 0.49, and 0.48, respectively, the wear mechanism is primarily oxidation wear, adhesive wear and abrasive wear, accompanied with fatigue wear.