Effect of TiO2/Al2O3 film coated diamond abrasive particles by sol-gel technique

► The diamond abrasive grains were coated with the TiO2/Al2O3 film via sol-gel route. ► The incipient oxidation temperature of the coated diamonds in air atmosphere was higher 175 °C than that of the uncoated diamonds. ► The coated diamonds had better the mechanical properties than that of uncoated diamonds after sintering at 750 °C. ► For the vitrified bond grinding wheels, replacing the uncoated diamonds with the coated diamonds, the properties of the grinding wheels were improved.