Boron Nitride Sintered Plates & Crucibles from Leading China Suppliers | Quality Factory Manufacturing
High Temperature Stability
h-BN can withstand temperatures of up to 2000°C in an inert atmosphere and remains stable in an oxidizing environment up to 900°C.
c-BN does not convert to h-BN below 1400°C.
Thermal Property
h-BN has better thermal conductivity than aluminum oxide (parallel to c-axis: 400 W/m·K, perpendicular to c-axis: 30 W/m·K).
It exhibits a low coefficient of thermal expansion (h-BN: parallel to c-axis -2.7×10⁻⁶/°C, perpendicular to c-axis 38×10⁻⁶/°C).
Mechanical Property
h-BN has a low hardness (Mohs hardness ~2) and excellent machinability; c-BN has a hardness second only to diamonds.
h-BN exhibits excellent thermal shock resistance due to its low elastic modulus.
Electrical Property
h-BN is a high-quality insulator (resistivity > 10¹⁴ Ω·cm, dielectric constant ~ 4).
c-BN is a wide-bandgap semiconductor (bandgap width ~ 6.4 eV).
Chemical Inertness
Resistant to corrosion by molten metals (such as aluminum and copper), and does not react with acids/bases (except for concentrated sulfuric acid and molten alkali).
Frequently Asked Questions
What is the maximum temperature h-BN can withstand?
h-BN can withstand temperatures of up to 2000°C in an inert atmosphere and remains stable in an oxidizing environment up to 900°C.
At what temperature does c-BN convert to h-BN?
c-BN does not convert to h-BN below 1400°C, maintaining its structural integrity up to that limit.
How does the thermal conductivity of h-BN compare to aluminum oxide?
h-BN has superior thermal conductivity compared to aluminum oxide, measuring 400 W/m·K parallel to the c-axis and 30 W/m·K perpendicular to the c-axis.
What are the mechanical differences between h-BN and c-BN?
h-BN is soft with a Mohs hardness of approximately 2 and features excellent machinability and thermal shock resistance. Conversely, c-BN is extremely hard, ranking second only to diamonds.
Is h-BN an electrical conductor or an insulator?
h-BN is a high-quality electrical insulator with a resistivity greater than 10¹⁴ Ω·cm and a dielectric constant of approximately 4.
How chemically resistant is Boron Nitride?
Boron Nitride is highly inert. It resists corrosion by molten metals such as aluminum and copper, and does not react with acids or bases, with the exception of concentrated sulfuric acid and molten alkali.