| 摘要 |
1521202 Superconductors BBC BROWN BOVERI & CO Ltd 10 March 1976 [12 March 1975] 09498/76 Heading C7D [Also in Divisions B3 and H1] A method of making a stabilized superconductor containing filaments of superconductive material in which a composite slug is mechanically deformed followed by the formation of superconductive filaments by the diffusion of at least one material from the outside of the conductor into a filament of second material inside the conductor, in which the parent slug contains rods or wires 2 of the second material which are surrounded by a material 3, 4, 5, 1, permitting the diffusible material to diffuse therethrough, and in its outer region rods or wires 6 of good electrical conductivity surrounded by a material 7 forming a barrier to the diffusible material, with, between barriers 7 a material 5 permitting the diffusible material to diffuse therethrough. Material 2 is Niobium, materials 1, 3, 4, 5, 6 copper, and material 7 is tantalum. In a second embodiment, Fig. 2 (not shown), a copper slug contains vanadium filaments, and outer copper rods surrounded by barriers of tantalum. The diffusible material is tin. The parent slug is closed at the ends and hot and cold deformed until a wire of e.g. 0À5 nm diameter is obtained, tinned, and the tin allowed to diffuse at 400‹C into copper 5, 4 and 3 and super-conductor compound Nb 3 Sn is subsequently produced at 700‹C by the diffusion of tin into the niobium filaments. Superconductors based on Va 3 Ga and V 3 Si can be produced in a similar way. Components 1, 3, 4, 5 and (8, Fig. 2) can be of a bronze alloy. Components 6, (10) can be of silver or aluminium. Rods 2, (9) can comprise copper or bronze rods containing a large number of niobium or vanadium rods. The diffusion-blocking barrier material may be of tantalum, niobium, vanadium or an alloy of these, and their action is based on the slowly proceeding reaction of these materials with the diffusible material and their thickness. |
