What is Cubic Boron Nitride?
CBN is the cubic crystalline form of Boron Nitride (BN) that is synthesised under conditions of high pressure and high temperature. It reproduces the diamond structure (cubic lattice) while substituting the carbon atoms with alternating boron and nitrogen atoms.
Unlike diamond, which decomposes in air above approximately 800°C, CBN remains structurally intact up to 1 400°C and is chemically inert towards iron, steel and other iron-containing metals, making it suitable for high-temperature processing environments.
Structure and Material Properties
Crystal Structure: Cubic
Atomic Arrangement: Boron and nitrogen atoms alternate within a diamond-like lattice
Key Properties:
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Second highest hardness after diamond
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High thermal conductivity
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Stable at extreme temperatures
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Chemically inert towards iron alloys
Physical Properties
| Property |
Value |
| Chemical Formula |
BN |
| Density |
3.48 g/cm³ |
| Colour |
Transparent to pale yellow |
| Crystal Structure |
Cubic |
Mechanical Properties
| Property |
Value |
| Hardness (Vickers) |
4 500 kg/mm² |
| Compressive Strength |
3 500–4 000 MPa |
| Elastic Modulus |
700–900 GPa |
| Fracture Toughness |
6–7 MPa-m¹ᐟ² |
Thermal and Electrical Properties
| Property |
Value |
| Maximum Operating Temperature |
1 400–1 500°C |
| Thermal Conductivity |
400–1 000 W/m·K |
| Thermal Expansion Coefficient |
4.7 × 10⁻6 /°C |
| Electrical Resistivity |
>10¹⁶ Ω-cm |
| Dielectric Constant |
~7.0 at 1 MHz |
Available Products
We supply high-purity CBN in two main configurations:
Cubic Boron Nitride Powder
Finely milled for polishing, grinding and the production of high-performance ceramics.
Cubic Boron Nitride Particles
Coarser grains suitable for bonded abrasives, sintered tools and coatings.
Industrial Applications
1. Machining and Cutting Tools
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Suitable for hardened steels and high-temperature alloys such as Inconel or Titan
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Retains sharpness and dimensional precision
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Can be employed where diamond loses quality due to its affinity for iron
2. Grinding and Polishing
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Utilised in CBN grinding wheels for alloys meeting aerospace standards
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Delivers high-precision surfaces with reduced thermal damage
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Employed for extremely hard coatings and fine polishing
3. Thermal Management in Electronics
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Utilised in heat sinks and thermal interface materials
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Exhibits high thermal conductivity without electrical conduction
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Stable at high operating temperatures
4. Wear-resistant Components
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Bearings, seals, nozzles and cutting edges
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Resists abrasion, mechanical load and thermal shocks
5. Aerospace and Defence
6. Automotive Industry
Frequently Asked Questions (FAQs)
Q: What is the difference between CBN and diamond?
A: CBN is chemically more stable against iron and withstands higher temperatures without decomposing.
Q: Can CBN be used at extreme temperatures?
A: Yes, it functions up to 1 400–1 500°C in air, whereas diamond oxidises at approximately 800°C.
Q: How is CBN synthesised?
A: It is produced by subjecting hexagonal boron nitride (h-BN) to high pressure and high temperature, following the method employed in synthetic diamond production.
Q: Is CBN reusable or recyclable?
A: Yes, depending on the application, CBN particles and tools can be recovered and reprocessed.
Q: Are there different types of CBN?
A: Yes. The types differ in terms of purity, particle size, thermal conductivity and intended use (e.g. for abrasive applications or electronics).
Your CBN Supplier
Stanford Advanced Materials supplies high-purity, performance-verified cubic boron nitride. Their products are used worldwide in cutting tools, aerospace components, electronic thermal systems and various other applications. Contact Stanford Advanced Materials if you require bulk pricing, customised formulations or technical consultation.
Contact us for product specifications, quotations or customised formulations.
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