Material Boron nitride
Two structures.
The hexagonal structure is similar to graphite, but white, and has high heat and corrosion resistance. It is used for electrical insulation products for hot and corrosive environments, and as lubricant for low friction sealing.

The cubic structure (CBN) is similar to diamond, has a higher density (3.48 kg/liter), and has extreme hardness and high thermal conductivity. The main application is for tools and as grinding material.

The hexagonal structure is manufactured using hot pressing or pyrolytic deposition techniques, and formed by hot pressing. The cubic is formed by ultra-high pressing of a fine powder.
Danish Name Bornitrid
Products Protection tubes
Processes Powder technology
References Atlantic Equipment Engineers
H.C. Starck GmbH & Co. KG
Johnson Matthey GmbH
Price Boron nitride is an expensive material. Boron nitride powder (hexagonal, 99.9% purity) can be purchased for 1,400 DKK/kg. Depending on the quantities and the grade purchased, prices can be higher (up to 2600 DKK/kg).
Additional Info Boron nitride will oxidise above 1100C. This results in a thin glaze of boric oxide which retards further oxidation. Boron nitride begins to decompose above 1500C.
Max. use temperature: 1200C (oxidising);
Thermal conductivity: 160 W/mK.
Copyright © 1996, 97, 98 Torben Lenau