Departmental Papers (MSE)

Document Type

Journal Article

Date of this Version

February 2006


Copyright The American Ceramic Society. Reprinted from Journal of the American Ceramic Society, Volume 89, Issue 7, 2006, pages 2147-2153.


Dense machinable α-SiAlON/BN composites were fabricated by hot-pressing using turbostratic boron nitride (tBN) obtained from nitridation of melamine diborate. The tBN was added to the starting powders, or introduced as a coating that formed in situ on α-Si3N4 carrier powders during nitridation, and was subsequently converted to hexagonal boron nitride (hBN) during hot pressing by solution reprecipitation. These composites maintain high strength at 1000°C and their strength/hardness are much higher than similar composites prepared using commercial hBN powder, which yielded a coarser microstructure. Good machinability was achieved despite a flat R curve.



Date Posted: 05 October 2006

This document has been peer reviewed.