Preparation and characterization of SiO2–Al2O3–Na2O glass coated cBN abrasive particles via sol–gel route

SiO2–Al2O3–Na2O glass coated cubic boron nitride (cBN) abrasive particles were prepared by sol–gel technique. The results indicated that SiO2–Al2O3–Na2O glass was excellent material for oxidation protection of cBN abrasive grains because coefficient of thermal expansion of this glass closely matched that of cBN materials. The single particle compressive strength and impact toughness of this glass coated cBN abrasive particles were significantly increased. For the application of glass coated cBN abrasives to vitrified grinding wheels, it was evident that the glass coating provided high bonding strength between cBN abrasive grains and vitrified bond system.