Boron Nitride Material Information
Specifications
| Physical Properties | Metric | English | Comments |
|---|---|---|---|
| Density | 1.95 g/cc | 0.0704 lb/in³ | Typical |
| Water Absorption | 0.006 | 0.006 | 400 Hours, 100% RH |
| Open Porosity | 0.13 | 0.13 | |
| Color | White |
| Mechanical Properties | Metric | English | Comments |
|---|---|---|---|
| Hardness, Knoop | 16 | 16 | 100 g |
| Modulus of Elasticity | 20.6 GPa | 2990 ksi | Perpendicular to pressing direction |
| Modulus of Elasticity | 48.2 GPa | 6990 ksi | Parallel to pressing direction |
| Flexural Strength | 17.2 MPa | 2490 psi | Perpendicular to pressing direction |
| Flexural Strength | 20.6 MPa | 2990 psi | Parallel to pressing direction |
| Compressive Yield Strength | 41.3 MPa | 5990 psi | Parallel to pressing direction |
| Compressive Yield Strength | 51.7 MPa | 7500 psi | Perpendicular to pressing direction |
| Electrical Properties | Metric | English | Comments |
|---|---|---|---|
| Electrical Resistivity | Min 1e+015 ohm-cm | Min 1e+015 ohm-cm | |
| Dielectric Constant | 4.1 | 4.1 | 1 MHz |
| Dielectric Strength | 54 kV/mm | 1370 kV/in | |
| Dissipation Factor | Max 0.0002 | Max 0.0002 | At 1 MHz |
| Thermal Properties | Metric | English | Comments |
|---|---|---|---|
| CTE, Linear 1000°C | 0.4 μm/m-°C | 0.222 μin/in-°F | 25-1500ºC. Perpendicular to pressing direction |
| CTE, Linear 1000°C | 0.8 μm/m-°C | 0.444 μin/in-°F | 25-1500ºC. Parallel to pressing direction |
| Heat Capacity | 0.808 J/g-°C | 0.193 BTU/lb-°F | Value at 700°C is 1.846 J/g-K |
| Thermal Conductivity | 23 W/m-K | 160 BTU-in/hr-ft2-°F | Perpendicular to pressing direction |
| Thermal Conductivity | 28 W/m-K | 194 BTU-in/hr-ft2-°F | Parallel to pressing direction |
| Max Service Temperature, Air | 850 °C | 1560 °F | Oxidizing Atmosphere |
| Max Service Temperature, Inert | 2000-3000 °C | 3630-5430 °F | Inert/Vacuum |
NOTE: The information in this data sheet is for design guidance only. Forming methods and specific geometry could affect properties.
Overview
Hot-pressed BN is compacted at temperatures up to 2000°C and pressures up to 2000 psi to form a dense, strong engineering material that is easily machined. It is available in standard and custom hot-pressed shapes and has several unique characteristics and physical properties which make it valuable for solving tough problems in a wide range of industrial applications. This information is provided by Momentive Performance Materials.
There are four material grades of Boron Nitride with HBC and HBT being the highest purity hot-pressed boron nitrides commercially available. They are diffusion bonded and feature a low dielectric constant, minimal moisture pick-up, and low loss tangent which makes them ideal for electronic applications. Grade HBT, although lower in strength and density than HBC, is available in larger sizes, at lower cost, and usually with a shorter delivery schedule. Grade HBN uses small amounts of boric oxide as a binder and should be used in applications where hydration and thermal shock are not a concern. Grade HBR uses calcium borate as a binder and is less sensitive to moisture.
Thermal Management: The unique combination of being both an excellent electrical insulator and thermal conductor makes BN very useful as a heat sink in high power electronic applications. Its properties compare favorably with beryllium-oxide, aluminum-oxide and other electronic packaging materials, yet is easier to form and finish.
High Temperature Applications: Temperature stability and excellent resistance to thermal shock makes BN the material of choice in the toughest high temperature applications such as equipment for plasma arc welding, diffusion source wafers, and semiconductor crystal growth equipment & processing.
Molten Metal Handling: BN is inorganic, inert, non-reactive with halide salts and reagents, and is not wet by most molten metals and slags. These characteristics, combined with low thermal expansion, make it ideal for interface materials used in various molten metal processes.
Applications & Usage
- Filament Insulators
- Vaporizer Tubes
- Cathode Repellers
- Clamp Isolators
- Thermocouple Protection Sheaths
- Reaction Vessel Liners
- Electronic parts such as substrates, coil forms, heat sinks and prototypes
- Microwave Tubes
- Low Friction Seals
- High temperature furnace fixtures and supports
- Microcircuit Packaging
Industries Using This Material
- Semiconductor
- Energy
- Aerospace