Precision Ceramics, a division of McGeoch Technology, is a company dedicated to the engineering of technical ceramics. From procurement and supply through to technical design and specialist machining, we offer a complete service.
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Features of Solid Boron Nitride
A completely unique material, Solid Boron Nitride solves problems that could not possibly be tackled with other compositions such as Al2O3 or SiC.
Solid Boron Nitride fights off temperatures over 2,000°C and, depending on the grade, carries a dielectric strength of nearly 1000 volts/mil. Hot pressed in billet form, Solid Boron Nitride can easily be machined into rods, bars, plates and even custom shapes.
The highly exceptional characteristics of Solid Boron Nitride make it ideal for fixture or jig materials for sealing or brazing operations in induction, vacuum and atmosphere furnaces; for molten metal crucibles; heat sinks and high temperature insulators.
Solid Boron Nitride - Grade A
An excellent choice for all but the most severe refractory applications, Solid Boron Nitride Grade A is a high performance material possessing a glassy B2O3 binder that creates a hard and dense yet fully machinable product.
Applications of Solid Boron Nitride - Grade A
Typical applications of Solid Boron Nitride Grade A include:
- High temperature electrical insulators and vacuum furnace supports which require electrical resistivity, high temperature strength, thermal shock resistance and low chemical reactivity
- Crucibles and containers for high purity molten metals
- Insulators and source fixtures for ion implantation systems which require high temperature purity and electrical insulation
- Radar components and antenna windows which require exacting electrical and thermal properties
- Setterplates for the processing of other advanced materials which require stable, inert surfaces
- Nozzles for powdered metal spraying
Physical Properties of Solid Boron Nitride - Grade A
The physical properties of Solid Boron Nitride Grade A is outlined in the following table.
Table 1. Physical properties of solid boron nitride grade A
Properties
|
Description
|
Binder
|
Boric Acid
|
Binder Melting Point
|
550°C
|
MAXIMUM USE TEMPERATURE
|
|
Oxidizing vs. Inert
|
850°C (1800°C)
|
Specific Heat at 700°C (J/g°C)
|
1.610
|
Dielectric Strength (V/mil)
|
2400
|
Hardness-Knoop (kg/mm2)
|
15.51 - 24.19
|
Pressing Direction
|
Para (Perp)
|
Resistivity Ohm-cm RT
|
>1014 (>1015)
|
Loss Tangent at 8.8 GHz
|
|
Dielectric Constant at RT
|
|
THERMAL CONDUCTIVITY
|
|
(W/m/K) at 25°C
|
30.13 (33.71)
|
THERMAL EXPANSION COEFFICIENT
|
|
(RT to 1500°C) (in/in.°Cx10-6)
|
11.85 (3.12)
|
FLEXURAL STRENGTH (psi)*
|
|
at 25°C
|
11000 (16400)
|
at 1500°C
|
900 (1380)
|
Compressive Strength at 25°C
|
|
Density (g/cc minimum)
|
2.00
|
% Open Porosity
|
2.84
|
Oxygen %
|
4.0
|
B2O3 (%)
|
4.5
|
Calcium (%)
|
0.1
|
Other Impurities (%)
|
0.2
|
*Based on 4-pt bend test-Sample size = 51mm x 4mm x 3mm
This information has been sourced, reviewed and adapted from materials provided by Precision Ceramics.
For more information on this source, please visit Precision Ceramics.