Boron Nitride Ceramic High Bottom Melting Crucible

The crucible is produced by depositing pyrolytic boron nitride upon a mandrel having the shape of the desired crucible at a temperature of from about 1850° C. to about 2100° C. until a first layer of boron nitride of suitable thickness has been produced, interrupting the deposition of boron nitride upon the mandrel and lowering the temperature to below 1750° C., and then depositing additional boron nitride upon the mandrel at a temperature of from about 1850° C. to about 2100° C. to produce a second outer layer of boron nitride having a thickness greater than that of the inner layer. Features and Benefits of Boron Nitride ceramic 1. Easily Machinable 2. Exceptional Heat Resistance 3. High Thermal Conductivity 4. Low Thermal Expansion, Excellent Thermal Shock Resistance 5. Outstanding Electrical Insulation - even at high temperatures 6. High wet resistance to molten metals, slags and glass 7. Extreme Corrosion and Wear Resistance

Pyrolytic boron nitride is a grade of hexagonal boron nitride. It is produced by chemical vapor deposition process to create its solid body and all the boron nitride crystals grow parallel to the surface of which the vapor is deposited on. Due to the nature of CVD process, PBN parts generally are requested the wall thickness not more than 3mm. PBN is also a good choice for extremely high purity of boron nitride. 99.99% is the typical grade. The CVD process give this pyrolytic boron nitride almost perfect layered structure, which leads to nisotropic thermal conductivity, making it an ideal material to make crucibles for crystal growing. PBN Ceramic Applications： -Crystal growth (VGF, LEC Crucible) -Molecular Beam Epitaxy(MBE) Crucible -MOCVD Heater -PBN Infrared Window -Traveling Wave Tube (TWT) (PBN Support Rod) -PBN Coating Graphite -High temperature, vacuum equipment insulator

MBE Crucible: 1. Product Instruction Molecular Beam Epitaxy(MBE) is mainly for crystal epitaxial growth MBE crucible is mainly applied as beam source crucible in MBE. 2. Product Feature >High purity (99.999%) >Low outgassing in high temperature >Uniform thickness, Good consistency in heating >Excellent thermal conductivity and shock resistance >Easy cleaning and Reusability >Inert, no reaction with acid and alkali

Boron nitride can be long-term used at 1800 degrees under vacuum atmosphere. With gas protection, Boron Nitride can be used at 2100°. Boron Nitride is with high thermal shock resistance, no cracks under extreme cold & high temperature. If you take out Boron Nitride from 1000 degree furnace and colding it within short minutes. It still won't break even repeat this test with 100 times. Material Properties： * High thermal conductivity * Excellent thermal shock resistance * Low thermal expansion * Exceptional heat resistance * Good Chemical Inertness * High electrical resistance * Low dielectric constant and loss tangent * High volume resistivity * Excellent machinability Grades 5 grades of boron nitrides are involved in Boron Nitride product series. * BN99 ● CABN ● ALBN ● ZRBN ● ZABN ● SB