Tungsten as Plasma-Facing Armour
The refractory metal of choice for the highest heat-flux surfaces.
- Use
- High-flux armour
- Property
- Highest melting point
Tungsten has the highest melting point of any metal, low erosion and low tritium retention, making it the reference armour for divertor targets and high-flux first-wall areas. Its brittleness and activation are managed through design and grade selection.
It faces the harshest conditions in the machine and is designed to be inspected and replaced.
Common questions
It has the highest melting point of any metal, low erosion and low fuel retention, which is why it is the international reference armour for the highest-heat-flux surfaces.
It is brittle and, as a high-Z metal, radiates strongly if it reaches the core — so it is used as a thin armour on a tougher heat sink and kept out of the confined plasma.