Technology for Transfer
Laser welding technology for niobium components of superconducting cavities

At Cryomodule Engineering Section/CCDD and Laser Development & Industrial Applications Division of RRCAT, a novel technology has been developed, which uses laser welding, instead of conventionally used electron beam welding technique (EBW), to weld niobium components of superconducting radio frequency (SCRF) cavities. This technology has certain novel features which may result in lower cost of welding while fabricating superconducting cavities. Patent has been granted for this technology from US patent office, Japanese and European Patent office.

Main Features
  • Capability to weld up-to 3mm of Niobium with a heat affected zone (HAZ) of 1 mm
  • Minimal damage to superconducting properties (RRR degradation < 10%), due to welding.
  • SCRF cavity fabricated with laser welding technique gave a performance similar to an electron beam welded cavity when tested at cryogenic temperature.
  • Capital & operating cost estimated to be significantly lower than EBW technique.
  • Welding performed in argon environment (1atm) instead of vacuum as in EB welding
Laser Weld Rig
Single Cell laser welded SCRF cavity
Laser Welding Rig
Single Cell laser welded SCRF cavity

The invention is directed to selective pulsed laser beam welding of the Niobium and its alloy based components for the fabrication of SCRF cavity with selective combinations of keyhole and conduction welding to achieve large penetration depth with minimum heat affected zone (HAZ), minimizing distortion and shrinkage and reduced weld time and costs.

Industries interested in establishing facility for welding niobium components of SCRF cavity by this technique may contact:

Dr. Sendhil Raja S.
Head, Technology Transfer Cell
Raja Ramanna Centre for Advanced Technology
Indore - 452 013 M.P.
Email:sendhil (at)
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