| 摘要 |
<p>1450360 Abrasive articles CINCINNATI MILACRON Inc 17 June 1974 [15 June 1973] 26681/74 Heading C4V An abrasive article having an abrasive portion comprising an abrasive phase comprising cubic boron nitride grain and a vitreous matrix bonding the abrasive phase, the vitreous matrix having a coefficient of thermal expansion substantially equal to that of the cubic boron nitride and being substantially non-reactive therewith, the surface of the cubic boron nitride interfacing with the vitreous matrix having formed thereon an adherent layer of boric oxide through which a strong bond is established between the boron nitride and the vitreous matrix. Preferably the abrasive phase comprises up to 90% of a second abrasive grain, the second abrasive grain preferably having a coefficient of thermal expansion substantially the same as that of the thermal expansion of the vitreous matrix and thus the cubic boron nitride. Suitable such materials are silicon carbide tungsten carbide, titanium carbide, boron carbide, zirconium carbide, tungsten boride, titanium boride, zirconium boride, tungsten nitride, titanium nitride and zirconium nitride. Preferably the volume ratio of the cubic boron nitride to that of the second abrasive grain is approximately 30 : 50.</p> |
