A titania/alumina (TiO2/Al2O3) film was coated on surface of diamond abrasive particles via a sol-gel technique. The effects of TiO2/Al2O3 film on the properties of diamonds and diamond/glass composites were investigated. The results showed that the TiO2/Al2O3 film could effectively improve the oxidation resistance of diamond, where the initial oxidation temperature of diamond was 600 οC in an air environment while oxidation of the TiO2/Al2O3 film coated diamond could not be found below 775 οC. For a mechanical property investigation, the TiO2/Al2O3 film coated diamond had a better compressive fracture strength (CFS) than that of the uncoated diamond after sintering. When the surface of a diamond was coated with a TiO2/ Al2O3 film, the contact angle between liquid glass and diamond film decreased from 105ο to 60 ο at 750 οC. For the application of the TiO2/Al2O3 film coated diamond to diamond/glass composites, it was evident that the performance of the composites was improved.

Keywords: Diamond, TiO2, Al2O3, Sol-gel, Glass