Metal treatment – Compositions – Heat treating
Patent
1982-12-30
1986-12-16
Skiff, Peter K.
Metal treatment
Compositions
Heat treating
29599, 148 115P, 148 115Q, H01L 3924
Patent
active
046295151
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to superconductive materials which are hardly deteriorated in superconductive characteristics even when deformed by mechanical stress and which can be produced on commercial scale, and a process for the production of superconductive substances which are to be used in the production of such superconductive materials.
BACKGROUND ART
Utilization of superconductive equipment in a wide variety of applications--e.g., as apparatus associated with the generation of energy, such as a nuclear fusion reactor, a superconductive generator, and an apparatus for the storage of electric power; high energy physical apparatus, such as an accelerator; transportation equipment such as a magnetic floating train and an appratus for propelling ships; and medical apparatus, such as an apparatus for treating diseases using .pi.-meson--has been gradually realized. With a great advance in such equipment and the production of large sized apparatus, it has been desired to develop superconductive materials which are capable of withstanding high magnetic fields and high-speed excitation.
For example, in magnetic fields as high as at least 8 tesla, there are usually employed superconductive wires which are made of compounds, such as Nb.sub.3 Sn and V.sub.3 Ga, having excellent high magnetic field characteristics. These wires, however, have the disadvantage that they are mechanically brittle. Therefore, various improved processes for the production of such superconductive wires have been proposed to overcome the above-described problem. For example, discontinuous fiber-shaped superconductive wire materials have been produced. These superconductive wire materials are produced by a process comprising solidifying a copper-base alloy containing low concentrations of niobium and tin components by rapidly cooling to finely disperse niobium particles in the matrix of copper, drawing the thus-formed alloy to form niobium fibers, and then applying heat treatment on the surface of the niobium fiber to form Nb.sub.3 Sn, or alternatively, a process comprising press sintering a mixture of niobium powder and copper and tin powders, or a coppertin alloy powder, producing fine short fibers, and then applying heat treatment on the surface of the fine short fiber to form Nb.sub.3 Sn.
In the discontinuous fiber-shaped superconductive wire materials produced by the above-described processes, eletric current is allowed to pass therethrough by the adjacent effect of discontinuous fiber-shaped superconductive substances. Therefore, even if the wire materials are deformed by the action of electromagnetic force, their superconductive current characteristics are not reduced as long as the distance between the superconductive substances is maintained at a lower level than a predetermined value.
In order to produce the above-described excellent discontinuous fiber-shaped superconductive wire materials or superconductive materials, it is necessary to use powdery or short fiber-shaped superconductive substances having excellent superconductive characteristics. An industrial method of production of such superconductive substances has not yet been established.
DISCLOSURE OF INVENTION
An object of the invention is to provide a process permitting industrial production of powdery or fibrous superconductive substances having excellent superconductive characteristics.
Another object of the invention is to provide excellent superconductive materials which are made of superconductive substances produced by the above-described process.
Superconductive substances include A 15 type compounds, such as Nb.sub.3 Sn, Nb.sub.3 Ge, Nb.sub.3 Al, V.sub.3 Ge, V.sub.3 Ga, and V.sub.3 Si, C 15 type compounds, such as HfV.sub.2, NaCl type compounds, such as NbC and NbN, oxides, such as BaPb.sub.1-x Bi.sub.x O.sub.3 and Li.sub.1+x Ti.sub.2-x O.sub.4, and Chevrel phase compounds, such as PbMo.sub.6 S.sub.8. These substances are used in a powdery or fibrous form in which the side or diameter is from several microns to several ten Angstroms (.
REFERENCES:
patent: 3763553 (1973-10-01), Barber et al.
patent: 4050147 (1977-09-01), Winter et al.
patent: 4073666 (1978-02-01), Marancik et al.
patent: 4084989 (1978-04-01), Meyer
patent: 4103075 (1978-07-01), Adam
patent: 4223434 (1980-09-01), Wang et al.
patent: 4242536 (1980-12-01), Young
patent: 4323402 (1982-04-01), Tachikawa et al.
patent: 4411959 (1983-10-01), Braginski et al.
patent: 4419125 (1983-12-01), Charles et al.
Suenaga et al, Filamentary A15 Superconductors, Roberge et al., "In Situ and Powder Metallurgy Multifilamentary Superconductors Fabrication and Properties", Plenum Press, N.Y., 1980, pp. 241-257.
Madsen et al., "The Effect of Heat Treatment on the Superconducting Properties of a Multifilamentary Nb.sub.3 Sn composite", IEEE Transactions on Magnetics, vol. Mag-15, No. 1, Jan. 1979, pp. 182-184.
Arihama et al, "Nb-Al Multifilamentary Superconducting Composites Produced by Powder Processing", Appl. Phys. Lett. 37(12), Dec. 1980, pp. 1107-1109.
Imaizumi Mitsuyuki
Yoshizaki Kiyoshi
Mitsubishi Denki & Kabushiki Kaisha
Skiff Peter K.
LandOfFree
Superconductive materials and process for the production thereof does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Superconductive materials and process for the production thereof, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Superconductive materials and process for the production thereof will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-243946