	US 7,566,414 B2
	Method for manufacturing power-metallurgy processed Nb3Sn superconducting wire, precursor to powder-metallurgy processed Nb3Sn superconducting wire
Takayoshi Miyazaki, Kobe (Japan); Takayuki Miyatake, Kobe (Japan); Hiroyuki Kato, Kobe (Japan); and Kyoji Zaitsu, Kobe (Japan)
Assigned to Kabushiki Kaisha Kobe Seiko Sho, Hyogo (Japan)
Filed on Mar. 06, 2006, as Appl. No. 11/367,459.
Claims priority of application No. 2005-086575 (JP), filed on Mar. 24, 2005.
Prior Publication US 2006/0216191 A1, Sep. 28, 2006
Int. Cl. B22F 5/12 (2006.01); H01L 39/24 (2006.01)

U.S. Cl. 419—8 [419/23; 419/46; 148/98; 505/432]

13 Claims

1. A method for manufacturing a powder-metallurgy processed Nb₃Sn superconducting wire, the method comprising the steps of:

filling a sheath made of Nb or a Nb alloy with a raw material powder containing Sn;

reducing a diameter of the sheath filled with the raw material powder to form a wire; and

heat-treating the wire to form a superconducting phase at an internal surface of the sheath,

wherein the raw material powder contains a Cu—Sn alloy powder or a Cu—Sn intermetallic compound powder and a Sn powder, and is compacted under isotropic pressure before the step of filling the sheath, and

wherein the Sn content in the Cu—Sn alloy powder or the Cu—Sn intermetallic compound powder is in a range of about 20 to 80 mass %, and the Sn powder is contained in the raw material powder at a mass ratio of about 0.2 to 2.0 relative to the Cu—Sn alloy powder or the Cu—Sn intermetallic compound powder.