https://doi.org/10.1140/epjs/s11734-026-02294-y
Regular Article
Advanced RF cavity manufacturing using multi-material laser powder bed fusion
1
Institute for Applied Physics and Measurement Technology, University of the Bundeswehr Munich, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
2
Institute for Design and Production Engineering, University of the Bundeswehr Munich, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
3
Fraunhofer Institute for Casting, Composite and Processing Technology IGCV, Fraunhofer Society, Am Technologiezentrum 10, 86159, Augsburg, Germany
4
Galvano-T electroforming-plating GmbH, Raiffeisenstraße 8, 51570, Windeck, Germany
a
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Received:
29
September
2025
Accepted:
21
March
2026
Published online:
30
March
2026
Abstract
Radio frequency quadrupoles (RFQs) are essential components of linear accelerators (Linacs) but remain challenging to manufacture using conventional techniques. Additive manufacturing (AM) offers the potential to lower production costs and enhance RFQ performance. However, vacuum sealing of AM cavities has so far been restricted to concepts without knife edges, limiting Linac applications. We present an RFQ prototype fabricated as a monolithic multi-material structure with a CuCr1Zr inner cavity and a tool-steel outer shell using laser powder bed fusion (PBF-LB/M). Compared to a previously reported prototype, optimized process parameters yielded a relative transition-zone density of about 99.7%, enabling a helium leak rate in the order of 
. To enhance the quality factor 
, the cavity surface was electropolished to reduce surface roughness and subsequently plated with pure copper to increase conductivity. A final of approximately 3100 was achieved. These results demonstrate significant progress toward vacuum-compatible, high-performance RF cavities produced via PBF-LB/M.
© The Author(s) 2026
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