Copper/niobium composite piping material produced by copper electroforming, process for producing the same and superconducting acceleration cavity produced from the composite piping material

摘要

In order to produce industrially advantageously an electroformed copper/niobium composite piping material wherein an electroformed copper layer and a niobium thin piping material are strongly bonded to each other, the electroformed copper/niobium composite piping material can be produced by coating any one or each of the outer peripheral surface and the inner peripheral surface of a niobium thin piping material with a nickel thin film, coating the surface of the nickel thin film with copper by electroforming, and subsequently annealing the resultant.