Boron Nitride is an advanced synthetic ceramic material available in solid and powder form. Its unique properties – from high heat capacity and outstanding thermal conductivity to easy machinability, lubricity, low dielectric constant and superior dielectric strength – make boron nitride a truly outstanding material.
In its solid form, boron nitride is often referred to as “white graphite” because it has a microstructure similar to that of graphite. However, unlike graphite, boron nitride is an excellent electrical insulator that has a higher oxidation temperature. It offers high thermal conductivity and good thermal shock resistance and can be easily machined to close tolerances in virtually any shape. After machining, it is ready for use without additional heat treating or firing operations.
In inert and reducing atmospheres, the AX05 grade of Boron Nitride grades will withstand temperatures over 2,000°C. It is commonly used as an insulator in contact with tungsten and graphite electrodes at those temperatures.
All Boron Nitride grades can be used in oxidizing atmospheres up to 750°C. It is not wet by most molten metals and slags and can be used in contact with most molten metals including aluminum, sodium, lithium, silicon, boron, tin, germanium, and copper.
General Boron Nitride Properties
To make solid shapes, BN powders and binders are hot-pressed in billets up to 490mm x 490mm x 410mm at pressures up to 2000 psi and temperatures up to 2000°C. This process forms a material that is dense and easily machined and ready to use. It is available in virtually any custom shape that can be machined and has unique characteristics and physical properties which make it valuable for solving tough problems in a wide range of industrial applications.
● Excellent thermal shock resistance
● High electrical resistivity – excluding aerosols, paints, and ZSBN
● Low density
● High thermal conductivity
● Anisotropic (thermal conductance is different in different planes relative to pressing direction)
● Corrosion resistant
● Good chemical inertness
● High temperature material
● Non-wetting
● High dielectric breakdown strength, >40 KV/mm
● Low dielectric constant, k=4
● Excellent machinability
Boron Nitride Applications
● Break rings for continuous casting of metals
● Break rings for continuous casting of metals
● Heat treatment fixtures
● High temperature lubricant
● Molds/mold release agent
● Molten metals and glass casting
● Nozzles for transfer or atomization
● Laser nozzles
● Nuclear shielding
● Induction heating coil supports
● Spacers
● High-temperature & high-voltage electrical insulators
● Furnace supports which require electrical resistivity
● Crucibles and containers for high purity molten metals
● Radar components and antenna windows
● Ion thruster discharge channels
Post time: Jul-14-2023