Feasibility study of the DEMO divertor target baffles

The divertor is one of the key components of a Tokamak fusion machine since it must be capable to exhaust both particles and power. Since the CAD model has been released the DEMO Outboard Vertical Target baffles (OVT) represent one of the most challenging components both from the design and fabrication technology point of view. It is infact exposed to intense neutron damage and high heat fluxes and has a very narrow radius of curvature (around 100mm compared to the radius of 500mm of ITER ones). Within the Work Package Divertor (WP-DIV 2021-2027) the EUROfusion Consortium launched a dedicated R&D task to explore the fabrication of the component itself. ENEA that is involved in the R&D technology activities of the target PFCs for the WP-DIV will study two alternative joining technologies with the aim to design and manufacture a mock-up made by a curved CuCrZr cooling pipe and Tungsten monoblocks joined to the pipe itself. The first technology is the well assessed Hot Radial Pressing (HRP) while the second one will be the brazing through an interlayer material between the pipe and the monoblocks. This paper reports the results of both joining technologies by means of Non-Destructive Examinations (Ultrasonic Testing) to give preliminary feedback on a suitable and industrially scalable manufacturing process.