For example, for particularly exposed areas of the plasma vessel, such as the divertor and the first wall, materials and coatings are being developed which are heat-resistant, thermally conductive, and resistant to physical and chemical erosion.
What is most important for the material performance in a power plant is the load exerted by the high-energy fusion neutrons. They penetrate the first wall and the blanket, where they deposit their energy. In the process they activate the materials and induce perturbations such as swelling, creepage, solidification, and embrittlement.
The objective of development work – in Germany primarily at Karlsruhe Institute for Technology (KIT) – is materials with high resistance and low activation. Their composition should make activation as low and quickly decaying as possible, thus allowing simple re-use or disposal.