Available as Finished Parts or Machinable Blanks Saint-Gobain Advanced Ceramics can provide custom machining of Combat® Solid Boron Nitride for complex shapes based on customer specifications

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UNIVERSITA’ DEGLI STUDI DI PISA 172

APPENDICE A

A.1 BN grado AX05

Grade AX05 Combat® BN Solids

Grade AX05 Combat® Boron Nitride Solids High purity plus unlimited machinability

Combat® Boron Nitride Solids, Grade AX05 is one of the highest purity hexagonal boron nitride solids available and a wise choice for applications where corrosion resistance is more important than wear resistance. It is a diffusion bonded ceramic and does not depend on B2O3 to other binders for mechanical integrity and, consequently, it is non-wet by almost all molten metals. This ultra purity advantage allows for applications and uses not provided by other hot pressed boron nitride solids, such as crucibles for high-purity molten metals. Commonly used in applications that demand very high thermal conductivity such as nozzles with small orifices.

Applications

• High temperature electrical insulators and vacuum furnace supports which require electrical resistivity, high temperature strength, thermal shock resistance and low chemical reactivity.

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• Crucibles and containers for high purity molten metals Insulators and source fixtures for ion implantation systems which require high temperature purity and electrical insulation.

• Setterplates for the processing of other advanced materials which require stable, inert surfaces.

• Nozzles for powdered metal spraying.

Available as Finished Parts or Machinable Blanks

Saint-Gobain Advanced Ceramics can provide custom machining of Combat®

Solid Boron Nitride for complex shapes based on customer specifications. Solid bars, rods and plates are also available for customers who desire to fabricate their own custom shapes using conventional machine shop tools.

Technical Properties

Binder: None

Binder Melting Point: None

Maximum Use Temperature

Oxidizing: 850°C

Inert: >2000°C

Specific HeatJ/g°C: 0.35

Dielectric Strength: 1000 V

Pressing Direction Para (Perp)

Resistivity Ohm-cm RT: >10¹⁴ (10¹⁵)

Loss Tangent @ 8.8 GHz: .0012 (.0003)

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Dielectric Constant @ RT: 4.0 (4.0)

Thermal Conductivity

(W/m/L) @ 25°C: 78 (130)

Thermal Expansion Coefficient

(RT to 1500°C) (in/in/°C x 10^-6):1.0 (0.3) Flexural Strength (psi)*

@ 25°C 2600 (3100)

@ 1500°C 6200 (11000)

Density (g/cc min.): 1.85

% Open Porosity: 12.57%

Oxygen - max.: 1%

Carbon - max.: 0.02%

Calcium - max.: 0.04%

Other Impurities - max.: 0.05%

*Based on 4-pt bend test-Sample size = 51mm x 4mm x 3mm.

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A.2 BN grado HP

Grade HP Combat® BN Solids

Grade HP Combat® Boron Nitride Solids

High thermal shock plus high thermal conductivity

When higher thermal shock, more spall resistance and lower permanent expansion upon heating is required, Combat® Boron Nitride Solids, Grade HP is a superior solid grade for formulations of <1000°C. Additionally, Grade HP has ten times the moisture resistance of Grade A due to the addition of calcium which combines with boric oxide to form calcium borate. Commonly used for many light metal

applications such as Al, Ti, Mg and Zn.

Applications

• 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

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• Nozzles for powdered metal spraying

Available as Finished Parts or Machinable Blanks

Saint-Gobain Advanced Ceramics, Boron Nitride products, can provide custom machining of Combat Solid Boron Nitride for complex shapes based on customer specifications. Solid bars, rods and plates are also available for customers who desire to fabricate their own custom shapes using conventional machine shop tools.

Thermal Conductivity as a Function of Pressing Direction

Typical Properties

Binder: Boric Acid

Binder Melting Point: 550°C

Maximum Use Temperature

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Oxidizing vs. (Inert): 850°C(1150°C*)

Specific Heat @ 700°C (J/g°C):1.468

Dielectric Strength (V/mil): 1700

Hardness-Knoop (kg/mm²) 13.79-18.95

Pressing Direction: Para (Perp)

Resistivity Ohm-cm RT: >10¹⁴ (>10¹⁵)

Loss Tangent @ 8.8 GHz: .0014 (.0007)

Dielectric Constant @ RT: 4.30 (4.02)

Thermal Conductivity

(W/m/K) @ 25°C: 27.0 (29.0)

Thermal Expansion Coefficient

(RT to 1500°C) (in/in/°C x 10^-6) 2.95 (0.87)

Flexural Strength (psi)*

@ 25°C : 6430 (8730)

@ 1500°C: 1710 (2470)

Compressive Strength

@ 25°C: 4370 (6460)

Density (g/cc minimum): 2.0

Open Porosity (%): 3

Oxygen (%): 5

B2O3 (%): 1

Calcium (%): 2.5

Other Impurities (%): 0.2

*Based on 4-pt bend test-Sample size = 51mm x 4mm x 3mm.

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A.3 AlN grado HP