What Is Cubic Boron Nitride?
CBN is the cubic crystal form of boron nitride (BN), produced synthetically under high-pressure, high-temperature conditions. It mimics the diamond structure (cubic lattice) but replaces carbon atoms with alternating boron and nitrogen atoms.
Unlike diamond, which degrades in air above ~800°C, CBN remains structurally intact up to 1400°C, and is chemically inert to iron, steel, and other ferrous metals, making it ideal for high-temperature machining environments.
Structure & Material Characteristics
Crystal Structure: Cubic
Atomic Arrangement: Boron and nitrogen atoms alternate in a diamond-like lattice
Key Traits:
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Exceptional hardness (second only to diamond)
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High thermal conductivity
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Stable at extreme temperatures
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Chemically inert with ferrous alloys
Physical Properties
| Property |
Value |
| Chemical Formula |
BN |
| Density |
3.48 g/cm³ |
| Color |
Transparent to pale yellow |
| Crystal Structure |
Cubic |
Mechanical Properties
| Property |
Value |
| Hardness (Vickers) |
4500 kg/mm² |
| Compressive Strength |
3500–4000 MPa |
| Young’s Modulus |
700–900 GPa |
| Fracture Toughness |
6–7 MPa·m¹ᐟ² |
Thermal & Electrical Properties
| Property |
Value |
| Max Working Temperature |
1400–1500°C |
| Thermal Conductivity |
400–1000 W/m·K |
| Thermal Expansion Coefficient |
4.7 × 10⁻⁶ /°C |
| Electrical Resistivity |
>10¹⁶ Ω·cm |
| Dielectric Constant |
~7.0 at 1 MHz |
Products Available
We offer high-purity CBN in two main forms:
Cubic Boron Nitride Powder
Finely milled for polishing, grinding, and advanced ceramics manufacturing.
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Particle size customizable
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High purity
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Suitable for electronics, coatings, polishing systems
Cubic Boron Nitride Particles
Larger grains ideal for bonded abrasives, sintered tools, and coatings.
Industrial Applications
1. Machining and Cutting Tools
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Ideal for hardened steels and high-temperature alloys like Inconel or titanium
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Maintains sharpness and dimensional accuracy
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Performs where diamond degrades due to iron affinity
2. Grinding & Polishing
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Used in CBN grinding wheels for aerospace-grade alloys
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Delivers high-precision finishes with reduced heat damage
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Popular in ultra-hard coatings and fine polishing
3. Thermal Management in Electronics
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Used in heat sinks and thermal interface materials
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Excellent thermal conductivity without electrical conduction
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Stable under high operating temperatures
4. Wear-Resistant Components
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Bearings, seals, nozzles, and cutting edges
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Withstands abrasion, mechanical stress, and thermal shock
5. Aerospace and Defense
Case Study: Stanford Advanced Materials Provided CBN Solutions for Aerospace Tooling
6. Automotive Industry
Frequently Asked Questions (FAQs)
Q: How is CBN different from diamond?
A: CBN is more chemically stable with iron and withstands higher temperatures without degradation.
Q: Can CBN be used at extreme temperatures?
A: Yes, up to 1400–1500°C in air, unlike diamond which oxidizes around 800°C.
Q: How is CBN synthesized?
A: By subjecting hexagonal boron nitride (h-BN) to high pressure and high temperature, similar to 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 grades of CBN?
A: Yes. Grades vary by purity, grain size, thermal conductivity, and intended use (e.g., abrasive vs. electronics-grade).
Your Trusted CBN Supplier
At Stanford Advanced Materials, we provide high-purity, performance-optimized Cubic Boron Nitride materials. Our products are used globally in cutting tools, aerospace components, electronic thermal systems, and more. Contact us for bulk pricing, customization, or technical consultation.
Contact Us for product specs, quotes, or custom formulations.
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