COMPOSITE SINTER OF SILICON NITRIDE/BORON NITRIDE & METHOD FOR MANUFACTURING THEREOF

摘要

A composite sinter of silicon nitride/boron nitride is created, which consists essentially of silicon nitride (60-97wt.%) and boron nitride (3-40wt.%), wherein the boron nitride is present as a dispersed phase in the network of silicon nitride. The composite sinter of silicon nitride/boron nitride is manufd. by kneading a silicon powder of 47.3-95.1 wt.% and a boron nitride powder of 4.9-52.7 wt.% as raw materials with an organic sovlent solution containing a dispersent and a binder; press-forming the kneaded mixture to prepare a green compact; sintering the green compact in a non-oxidizing atm. at 1100≦̸C-1300≦̸C to prepare a sinter having a strength permitting machining; machining the sinter into prescribed dimensions; and sintering the resultant machined sinter in a nitorogen atm. of 1250-1450≦̸C to nitrify the same, thereby improving the strength and thermal-shock resistance of the sinter.