The radiation shielding properties of pure tungsten
The radiation shielding properties of pure tungsten are difficult to fully exploited in small and complex shapes because of the cost and difficulty in machining. An addition of copper and nickel powders to tungsten powder creates tungsten heavy alloy (WHA) and improves the machinability. This WHA is a fully dense material with unique thermal and mechanical properties associated to sizeable radiation shielding properties.
With over 50 years experience in WHA, we can provide collimators and shielding material, vacuum compatible and compliant to ASTM B777.
| Material | Thermal Expansion (ppm/K) between 50 and 400 C |
Thermal Conductivity (W/m*K) at 25 C |
Density (g/cc) | Hardness (Rockwell C) |
Yield Strength at 0.2% offset (PSI) |
|---|---|---|---|---|---|
| W/Ni/Cu 90/6/4 wt% | 6.2 | 70 | 17.0 | 24 | 80000 |
| W/Ni/Cu 95/3.5/1.5 wt% | 5.2 | 75 | 18.2 | 27 | 85000 |
- Homogeneous material in 3 directions with no voids on the surface.
- Vacuum compatible because of low outgassing.
- Not magnetic.
- Uniform Gold plating.
- Mechanical tolerances of final parts better than 0.001” (0.025 mm).
- Engineering support to design the suitable collimators and radiation shields geometry.
Although the density approaches that of tungsten, unlike tungsten WHA is readily machinable and displays superior mechanical properties as well as low thermal expansion:
The high density enables WHA’s superior performance compared to lead and other lead replacements in radiation shielding, x-ray and γ-ray collimation. Other uses include gyroscopic components, boring bars and armor piercing projectiles
The low expansion coefficient allows WHA to be compatible with certain glasses (pyrex), semiconductors (InP, InSb, Ge, GaP), metals (Kovar) and ceramics (alumina, sapphire and aluminum nitride)
Applications
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X-ray and γ-ray radiation shielding/ attenuation components such as collimators for medical, industrial and security applications
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Low thermal expansion coefficient materials for optoelectronics and fiber optics applications
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Low thermal expansion coefficient materials for silicon power electronics
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Kinetic energy penetrators