Boron Nitride Tube is a high-temperature ceramic tube made from HPBN or PBN material. It is used in vacuum furnaces, semiconductor heat treatment, thermocouple protection, molten metal contact and laboratory high-temperature equipment. It helps reduce cracking, sticking, contamination and insulation failure in processes where quartz, alumina or metal tubes may not be suitable.
Boron nitride ceramic tubes can be produced from different BN material systems, mainly including HPBN and PBN.
HPBN, or Hot Pressed Boron Nitride, is commonly used for structural ceramic parts, insulation tubes, protection sleeves and machinable ceramic components. It offers good thermal shock resistance, stable insulation and excellent machinability, making it suitable for custom tubes with specific OD, ID, length, holes, slots or end structures.
PBN, or Pyrolytic Boron Nitride, is usually selected for applications requiring higher purity, cleaner material contact and better process stability, especially in semiconductor, vacuum and high-purity thermal processing environments.
Unlike alumina ceramic tubes, boron nitride tubes are not mainly selected for hardness or wear resistance. They are more suitable for thermal shock resistance, low expansion, high-temperature insulation, non-wetting behavior with molten metals and use in vacuum or inert atmosphere environments.
For more material options, please view our Boron Nitride Ceramic products.
Boron nitride tubes are commonly used in high-temperature processes where fast temperature changes, electrical insulation, clean material contact or reduced molten metal adhesion are required.
Typical applications include:
Insulation and protection tubes for semiconductor heat treatment equipment
Thermal insulation tubes and protection sleeves for vacuum furnaces and atmosphere furnaces
Thermocouple and temperature sensor protection tubes
Components in contact with molten aluminum, zinc and certain glass materials
Metallurgical casting, molten metal handling and high-temperature test systems
Laboratory reactors and research equipment
High-temperature insulation parts for aerospace and R&D applications
Ceramic tube components for inert or controlled atmosphere systems
For semiconductor-related applications, please view our Semiconductor Ceramic Parts.
For other ceramic tube products, please view our Ceramic Tube collection.
Available in HPBN or PBN material systems for different purity and process requirements
Suitable for use up to around 1800°C in vacuum environments
Suitable for use up to around 2100°C in inert atmospheres
Low thermal expansion to help reduce thermal stress and cracking risk
Good thermal shock resistance for rapid heating and cooling conditions
Strong electrical insulation for high-temperature isolation applications
Non-wetting behavior with molten aluminum, zinc and certain glass materials
Excellent machinability; can be turned, drilled, slotted and threaded
Custom OD, ID, length, wall thickness, end faces, holes and slots available
CERAMPRO manufactures custom boron nitride tubes according to customer drawings or samples. These tubes are suitable for OEM equipment, semiconductor processes, vacuum furnace systems, metallurgical equipment, research devices and high-temperature industrial applications.
We can produce straight BN tubes, insulating sleeves, thermocouple protection tubes, furnace protection tubes, molten metal contact tubes and special BN tube structures. For products with specific requirements on OD, ID, tolerance, wall thickness, end face, holes, slots, threads or assembly design, we can evaluate the machining feasibility based on the drawing.
Because BN performance is closely related to the working atmosphere, we recommend confirming the actual operating conditions before production. Useful information includes working temperature, vacuum level, gas atmosphere, contact medium, heating and cooling rate, and installation method. This helps select the right BN material and reduce application risk.
| Parameter | Technical Indicator | Functional Significance |
|---|---|---|
| Material Type | HPBN (Hot Pressed Boron Nitride) / PBN (Pyrolytic Boron Nitride) | HPBN is used for general structural and machinable parts; PBN is suitable for high-purity applications |
| Max Service Temperature | 1800°C in vacuum / 2100°C in inert atmosphere | Suitable for high-temperature conditions where quartz or some alumina materials may not perform reliably |
| Thermal Conductivity | 30–100 W/(m·K) | Directional heat dissipation; actual value depends on BN grade and structure |
| Dielectric Strength | 25–40 kV/mm | Suitable for high-temperature electrical isolation and high-frequency induction applications |
| Expansion Coefficient | 0.5–4.0 × 10⁻⁶/K | Low expansion helps improve thermal shock resistance |
| Machinability | Excellent; standard tools can be used | Can be turned, drilled, slotted, threaded and machined to custom specifications |
| Wettability | Non-wetting / hydrophobic behavior | Molten aluminum, zinc and certain glass materials are less likely to adhere |
| Chemical Resistance | Excellent chemical inertness | Resistant to many acids, alkalis and molten halides, depending on actual conditions |
Note: The above values are typical reference data. Actual performance may vary depending on BN grade, tube size, wall thickness, machining method, working atmosphere, operating temperature, contact medium and assembly method. For long-term use in air or oxidizing atmospheres, the working temperature and service life should be evaluated separately.
| Material | Main Features | More Suitable Applications |
|---|---|---|
| HPBN | Good machinability, good thermal shock resistance and suitable for custom structural parts | Vacuum furnaces, thermocouple protection, molten metal contact and high-temperature insulation |
| PBN | Higher purity and dense structure for cleaner process environments | Semiconductor processes, high-purity heat treatment and vacuum high-temperature components |
| Alumina Ceramic | High hardness, good wear resistance, good insulation and relatively controlled cost | General insulation parts, furnace parts, wear parts and structural components |
| Quartz Glass | Good purity and thermal shock resistance, but lower mechanical strength | Laboratory equipment, observation tubes and high-purity process environments |
| Aluminum Nitride Ceramic | High thermal conductivity with electrical insulation | Heat dissipation parts, electronic substrates and semiconductor thermal management |
| Silicon Nitride Ceramic | High strength, good toughness and good thermal shock resistance | High-load structural parts, mechanical components and impact-resistant parts |
Boron nitride ceramic tubes are mainly used in vacuum furnaces, semiconductor heat treatment, thermocouple protection, molten metal handling, metallurgical equipment, laboratory reactors and high-temperature testing systems.
HPBN is hot pressed boron nitride and is suitable for general structural parts, insulation parts and custom machined components. PBN is pyrolytic boron nitride and is usually selected for semiconductor or high-purity process environments that require better purity and cleanliness.
Boron nitride tubes can be used up to around 2100°C in inert atmosphere environments. In vacuum environments, the typical maximum service temperature is around 1800°C. For air or oxidizing atmospheres, the working temperature should be evaluated separately.
BN is more suitable for vacuum, nitrogen, argon or other inert and controlled atmosphere environments. Long-term high-temperature use in air should be confirmed according to the actual temperature, atmosphere and service life requirements.
Alumina ceramic tubes are better for high hardness, wear resistance and general insulation. Boron nitride ceramic tubes are better for thermal shock resistance, low expansion, non-wetting behavior with molten metals, high-temperature insulation and use in vacuum or inert atmospheres.
Yes. BN ceramic has good dielectric strength and can be used for high-temperature electrical isolation, sensor protection, high-frequency induction applications and semiconductor equipment insulation structures.
BN has non-wetting behavior with molten aluminum, zinc and certain glass materials, so it is often used in metallurgy, casting and molten metal handling applications. Final suitability depends on the medium type, temperature and contact time.
Compared with high-hardness ceramics such as alumina or zirconia, boron nitride is easier to machine. It can be turned, drilled, slotted, threaded and end-machined for custom tube structures.
Yes. OD, ID, length, wall thickness, tolerance, end structure, holes, slots, threads and other machining details can be evaluated according to drawings or samples.
Please provide drawings or samples, material type, OD, ID, length, wall thickness, tolerance, quantity, working temperature, atmosphere, contact medium, heating and cooling conditions, and any special machining requirements.
