Performance assessment of thick W/Cu graded interlayer for DEMO divertor target

High-heat-flux technologies for the European demo divertor targets: State-of-the-art and a review of the latest testing campaign

“…1 shows the characteristic design features of the DEMO divertor target concepts. For the details of design rationales [16,17], design studies [18][19][20][21] and technology progress [22][23][24][25] achieved in the second R&D phase, readers are referred to the given references. For the sake of completeness, the underlying design logics of the selected target design concepts are briefly described again in what follows.…”

“… FGM interlayer: 20µm (PVD) vs. 500µm (cold-spray) [24]  Thermal break: spoke vs. circular bore [20]  Composite pipe: 150µm wire vs. 50µm wire [25] For FGM, cold spray method was used for fabrication of the thick coating because the deposition rate of PVD (magnetron sputtering) is too low to be practicable for producing a thick coating. For the thermal break, the spoke type geometry was replaced by circular bores to avoid rupture of the thin spokes due to plastic strain concentration.…”

Heat exhaust in fusion reactors and its impact on the sustainability of fusion electricity

“…Over the thickness, a smooth transition from a 100% to 0% W volume fraction is achieved, eliminating the abrupt discontinuity in the thermo-mechanical properties inside the material and reducing the stresses. Both FGM made of W/Fe [13], for the first wall, and W/Cu [14,15], for the divertor, are being developed. The integration of a solution in a component is currently being tested.…”

Preparation of W-Cu composites by infiltration of W skeletons – review

“…The largely different properties and operational temperature windows of these two materials present a major challenge, which can be alleviated by introducing an interlayer with intermediate properties, such as the composite [3]. This interlayer can also have a gradually varying composition, which further reduces the stress concentration [4,5,6].…”