Physical Properties of Performance PBN™

Performance PBN is a non-porous, opaque material with mechanical properties that are actually enhanced at high temperatures. Its crystalline structure- consisting of layers of hexagons composed of boron and nitrogen atoms stacked on top of each other in parallel planes-gives it good flexural strength, high compression strength and high fracture resistance. The bonds between the boron and nitrogen atoms vary with crystal direction, giving Performance PBN aniosotropic properties. In each ring in the planar ("a") direction, the nitrogen and boron atoms bond covalently. In the perpendicular ("c") direction, the bonds are formed by the weaker van der Waal's forces.

Directional Properties of PBN

Pyrolytic Boron Nitride's Hexagonal Structure

Summary of Mechanical Properties

PROPERTY	VALUE
Average Density	2.185 g/cc
Gas Permeability (Helium)	2 x 10-11 cm2/sec
Compression Strength "a" Direction @25°C	37,000 PSI
Compression Strength "a" Direction @1200°C	35,000 PSI
Compression Strength "c" Direction @25°C	48,000 PSI
Compression Strength "c" Direction @1200°C	54,000 PSI
Tensile Strength "a" Direction @25°C	21,000 PSI
Flexural Strength @25°C	28,000 PSI
Flexural Strength @1200°C	27,000 PSI
Torsional Shear Strength @25°C	93,000 PSI
Young's Modulus "a" Direction @25°C	3.4 x 106
Poisson's Ratio "a"Direction @25°C	.086
Flexural Modulus @25°C	3.2 x 106 PSI
Flexural Modulus @1200°C	3.2 x 106 PSI
Hardness Taken on surface of "a" plane Knoop Hardness #	75
"a" Directional Compressive Stress vs. Strain	Strain (%) in Addition to Strain at 20 KPsi Stress (KPsi)
Specific Heat vs.Temperature

Properties of Performance PBN

Physical

Thermal

Chemical / Electrical