First results of SRF cavity fabrication by electro-hydraulic forming at CERN

In the framework of many accelerator projects relying on RF superconducting technology, shape conformity and processing time are key aspects for the optimization of niobium cavity fabrication. An alternative technique to traditional shaping methods, such as deep-drawing and spinning, is Electro-Hydraulic Forming (EHF). In EHF, cavities are obtained through ultra-high-speed deformation of blank sheets, using shockwaves induced in water by a pulsed electrical discharge. With respect to traditional methods, such a highly dynamic process can yield valuable results in terms of effectiveness, repeatability, final shape precision, higher formability and reduced spring-back. In this paper, the first results of EHF on copper prototypes and ongoing developments for niobium for the Superconducting Proton Linac studies at CERN are discussed. The simulations performed in order to master the embedded multi-physics phenomena and to steer process parameters are also presented.