Pyrolytic Boron Nitride Ring | PBN Ring

Pyrolytic Boron Nitride (PBN) Ring

  supplied by QS Advanced Materials is produced by CVD process (chemical vapor deposition) 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, thick wall products (>3mm) is usually not available. PBN is also a good choice for extremely high purity boron nitride. As the purity of gas material  (BCl3 + NH3 --> BN +HCl) is a lot higher than regular boron nitride powder, purity for PBN is quite high and 99.99% is the typical grade.  With it's high purity, high mechanical strength, high performance with molten metal and salts, PBN is beacaming an widely used material in high vacuum processes. Without showing melting point and high thermal conductivity, pyrolytic material are ideal to be used as vacuum furnace parts.The CVD process give this pyrolytic boron nitride almost perfect layered strucuture, which leads to anisotropic thermal conductivity, making it an ideal material to make crucibles for crystal growing.  

The pyrolytic boron nitride rings QSAM could supply, are cut from 1mm 2mm or 3mm thick PBN rings with about 10~14" diameter. The diameter of raw material PBN was limited by equipment size but the finished PBN products could be machined to highly customized shape with competitive cost. 

Pysical properties of PBN

Boron Nitride Content	99.99%
Crystalline	hexagonal
Physical Properties	Along crystal plane (a)	Perpendicular crystal plane (c)
Lattice Constant	2.5x10-10m	6.8x10-10m
Flexural Strength MPa	60	N.A.
Tensile Strength MPa	>80	N.A.
Density	2.1 g/cm3
Hardness ~Knoop	11 kg/mm2
Thermal Conductivity 200C	82W/mK	2.6W/mK
Thermal Conductivity 900C	55.3W/mK	2.8W/mK
Thermal Expansion RT	2x10-6/K	15.5x10-6/K
Dielectric Constant	5.2	3.8
Dielectric Strength	59KV/mm
Electrical Resistance RT	>1014ohm cm

PBN Ring Applications

Pyrolytic boron nitride (PBN) rings, manufactured using the chemical vapor deposition (CVD) method, exhibit perfect layered hBN crystals that grow along their surfaces. This unique structure ensures uniform thermal conductivity throughout the ring, distinguishing it from hot-pressed BN or other ceramics. Additionally, the CVD process results in exceptionally high purity levels of PBN, reaching up to 99.99%. These properties make PBN rings an excellent choice for applications such as molecular beam epitaxy (MBE). In MBE equipment, PBN rings are commonly used as support materials for crucibles. The compatibility with PBN crucibles ensures a consistent performance and enables a contamination-free environment for the MBE process. The combination of PBN crucibles and rings provides a reliable and efficient solution for researchers and industries seeking optimal results in MBE applications.

List Of PBN Products QSAM supplies

PBN Disc/Sheet/Ring

PBNMachined Products and Custom Parts

PBN Crucibles(VGF/LEC/Conical/MBE)

PBN Packaging

As a ceramic material, boron nitride is quite fragile in a lot of cases. The PBN rings are usually hold in plastic bags by vacuum, and protect with heavy foam.