Material Use Guide for Boron Nitride

BASIC PROPERTIES OF BORON NITRIDE
(for pure material/fully dense; may differ from coating)

Formula Weight, BN......................................................................... 24.83
Density (Theoretical)............................................................... 2.27 g/cm³
Crystal Structure...................................................................... Hexagonal
Color................................................................................................... White
Emissivity (at 1300 K)............................................................................0.6
Dielectric Strength..................................................... 800-1000 volts/mil
Dielectric Constant................................................................................... 4
Coefficient of Friction..................................................................... 0.2-0.7
Electrical Resistivity (at 298 K).................................. 1.7x10¹³ ohm-cm
Knoop Microhardness (kg/mm²@100-g.load; at 298 K)................200
Thermal Expansion (Directional).............. 0.8-7.5x10^-6/C; 25-1000 C
Specific Heat (at 298 K)...................................................... 0.117 cal/g K
Thermal Conductivity
 (at 293 K, directional, avg.)........................ est. 0.08 cal / (cm-sec-K)
Use Temperatures ..............................................1800 C Reducing/Inert
.............................................................................................1400 C Vacuum
...........................................................................................1100 C Oxidizing
Melting ................................ > 2400 C (in nitrogen); sublimes >1800 C

COMPATIBILITY DATA

Reportedly Stable at High Temperatures
(Minimum Interaction)

Na, B, C, Fe, Ni (below melting), Al, Si, Cryolite, KBF₄, Li₂B₄O₇, Molten Halide Salts, Steels, Ge, Sb, In, Cu, Sn, Cd, Stainless Steels, Non-Lead Glasses, MoSi₂, W, ZrO₂ & Y₂O₃ (up to BN dissociation), Mg, Zn
 

Reacts at High Temperatures
(Unstable)

U, Ni (at melting), Pt, Ce, Be, Mo, CI₂, High-Leaded Glasses, MoO₃, Cr₂O₇, PbO_X, Sb₂O₃, As0₃, CuO, Bi₂O₃, Molten K₂CO₃/KOH

Data for the pure materials. Performance of the coatings may differ. Given for general information only; some interaction may occur at certain temperature and environmental conditions; it is advised that investigators evaluate their specific systems based on a thorough search of the literature. Many materials may be compatible/stable but were not known to us -- this list should not be considered exaustive.