Oxidation resistance

The first-wall materials must possess good oxidation resistance if it will withstand a loss-of-coolant accident scenario. We study corrosion performance using oxy-acetylene torch testing (right) and have developed and patented corrosion barriers for candidate WC-based materials (left).

SEM cross-sectional image of a Si-rich coating developed by pack cementation. The coating forms a two-part structure with WSix-rich inner layer and a FeSix outer layer, which provides excellent protection.

Fusion materials may be exposed to >1000 oC, making high temperature mechanical behaviour important. We try to understand potential mechanisms of failure, using techniques like dynamic flexural testing (left) and compressive creep (right).

Compressive testing of WC-FeCr composites to identify mechanistic retimes, showing 3 regimes of stress dependence, n
Material development

The extreme conditions of a fusion reactor exceed the capabilities of industrially available materials, requiring new structures and composites to be engineered. We have developed metal-ceramic composite shielding materials, including W2B-W (left) and WC-FeCr (right) in which the metallic phase offers improved fracture toughness and manufacturability.

Two W2B-W composites with different boron contents, W-16B and W-30B, which result in a trade-off between shieilding performance and damage tolerance. (a) EBSD phase maps, revealing the different boride phase fractions; (b) SEM images in BSE mode revealing the grain structure.