Fabrication of HCPB breeding blanket components using the additive manufacturing processes of selective laser melting and cold spray

Abstract

Different manufacturing routes are investigated at the KIT INR for the realization of First Walls (FW) and internal components for the Helium Cooled Pebble Bed (HCPB) nuclear fusion reactor component Breeding Blanket (BB). As result of cost estimation studies in 2017 and 2018, Additive Manufacturing (AM) has been identified to provide promising options beyond conventional technologies. Selective Laser Melting (SLM) and Direct Energy Deposition (DED) applied as Cold Spray (CS) were addressed. SLM was followed with focus on the development of BB internal structures. CS turned out as a very goal oriented and effective fabrication process with regard to the First Wall geometrical requirements. Further, a large potential for cost reduction compared to other technologies was identified. Based on a variation of the DED process CS applied in alternation with machining and an option for temporary filling cavities, an extended process chain was developed in collaboration with industry. This process chain also enables Laser structuring of internal channel surfaces for heat transfer enhancement structures. This paper summarizes the developments in terms of application of AM for the HCPB BB concept where SLM is focused as an option for BB internal structures assembled as hybrid components and CS addressed for fabrication of the First Wall.