Nb OR Nb-BASED ALLOY ROD FOR MANUFACTURE OF Nb3Sn SUPERCONDUCTING WIRE BY BRONZE METHOD, PRECURSOR FOR MANUFACTURE OF Nb3Sn SUPERCONDUCTING WIRE, ITS MANUFACTURING METHOD, AND Nb3Sn SUPERCONDUCTING WIRE

摘要

PROBLEM TO BE SOLVED: To provide a Nb or Nb-based alloy rod capable of improving the processability (especially, extrusion ratio) in the Nb or Nb-based alloy used when an Nb3Sn superconducting wire is manufactured, and also to provide the superconducting wire which exhibits excellent superconducting properties (especially, critical current and n value) using such the Nb or Nb-based wire rod, a precursor for manufacture of the superconducting wire, and its manufacturing method. SOLUTION: The Nb or Nb-based alloy rod for manufacture of the Nb3Sn superconducting wire rod is used for manufacturing the Nb3Sn superconducting wire by a bronze method. The recrystallization rate of a crystal structure on the vertical cross section passing the center point of the cross section and parallel to the longitudinal direction is 78% or more, and 0.2% value of the yield strength at room temperature is 220 MPa or less. COPYRIGHT: (C)2009,JPO&INPIT