materials

Boron Nitride (hBN)

Hexagonal Boron Nitride is a versatile material that boasts a high thermal conductivity, electrical resistivity, and high thermal shock resistance, while maintaining both low density and facile machinability.
4.0

Relative Cost of Material

7.5

Machining Degree of Difficulty

Summary

Hexagonal Boron Nitride is a versatile material that boasts a high thermal conductivity, electrical resistivity, and high thermal shock resistance, while maintaining both low density and facile machinability. It is corrosion resistant, and has a relatively high maximum working heat. While Boron Nitride has shares a number of physical characteristics with both Alumina and Aluminum Nitride, its structure and density make it significantly easier to machine, making it possible to machine complex geometries while still maintaining tight tolerances.

Mindrum Precision specializes in tight tolerance work in ceramics, glass, and metals, and we are a trusted leader in Boron Nitride machining. Not unlike the case with Macor, the main limiting factor when fabricating components out of hBN is the skill of the machinists in working with the material, and we have a decades-long track record of producing some of the tightest tolerance Boron Nitride components on the market. Click here for our contact information or to request a quote, and we will show you why more companies come to us for the parts that matter most.

Application

Aluminum Nitride is widely used for its thermal conductivity, and is a frequent replacement for Beryllium Oxide, due to the inherent health risks of working with BeO. More importantly from a functional standpoint, Aluminum Nitride has a significantly lower coefficient of thermal expansion than either Alumina or BeO, which allows for an optimal pairing with CTE-equivalent Silicon-based applications. Additionally, Aluminum Nitride is non-reactive with most process chemicals and gases, which makes it that much more desirable for use in the semiconductor industry. General applications include heat sinks, wafer carriers, substrates, crucibles, power transistor bases, and many other applications as well.

While thin Aluminum Nitride is fairly straightforward to machine using laser cutting techniques, machining thicker components from aluminum nitride can be extremely challenging for machining companies that do not specialize in this type of fabrication. Due to the physical properties of the material itself combined with its tendency to adhere to diamond tooling, hitting tight tolerances and working in more complex geometries is often beyond even conventional ceramic machining shops. At Mindrum Precision, we bring a superior level of precision technology to bear on your project that allows us to produce the results you need in all materials that we work with, and Aluminum Nitride is no exception. Contact us today, and we look forward to bringing your design off of the drawing board and into reality.

Properties

Material PropertyBoron Nitride
Density (g/cm^3)3.25
Hardness (Knoop)1170
Tensile Strength (MPa)0
Modulus of Elasticity (GPa)321
Flexural Strength (MPa)362
Compressive Strength (MPa)2068
Poisson's Ratio0.22
Fracture Toughness (MPa*m^.5)2.9
Dielectric Strength (ac-kV/mm)17
Dielectric Constant (@1MHz)8.0 - 9.0
Volume Resistivity (ohm-cm @25°C)> 1011 
Coefficient of Thermal Expansion (1 x 10^-6/°C)4.6 - 5.7
Thermal Conductivity (W/m K)100 - 180
Specific Heat (J/kg*K)780
Shock Resistance (°C Differential)220
Maximum Working Temperature (°C)1200
Index of Refraction0
Birefringence (No-Ne)0
Transmission Band Wavelength (μm)0

related Materials

  • Alumina – Harder, more corrosion resistant ceramic with similar CTE
  • Macor – Easily machinable ceramic with similar electrical resistivity
  • Aluminum Nitride – Harder, denser ceramic with similar electrical resistivity

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