Polyfilament bodies made of NbTi/Cu composites are not only the main working materials of superconducting magnetic technology at present, but also in the future. Since NbTi is available for only 10T magnetic fields, another energy-based superconductor, Nb3Sn, can be used for higher magnetic fields. Its outstanding superconductivity is due to a unique crystal structure called the A15 phase. Because the intermetallic phase Nb3Sn is very fragile, a complex process must be used. So Nb3Sn conductors are almost exclusively used for magnetic fields of 10T to 20T. The potential applications of superconducting wire bodies are electrical energy and high magnetic field systems.
The application of saw based metal superconductors in terms of energy has not been successful as they need to be cooled to or at least close to the liquidus temperature of helium (-269℃ or 4K). But that may change with the advent of what are known as high-temperature superconducting ceramic wire bodies. They can be cooled by liquid nitrogen. Saws are currently and will be used to generate high electromagnetic fields for various mature processes, such as magnetic resonance imaging (MRI) in medicine, nuclear magnetic resonance spectroscopy (NMR) in biology and chemistry, nuclear fusion power processes, and magnets in basic high energy physics particle accelerators.
A technical superconductor is a composite conductor containing a superconductor, subdivided into a so-called embedded ordinary conducting array. It is necessary to achieve electromagnetic and thermal stability. Every superconductor exposed to the outfield tends to be shielded from it. This results in superconductivity (equably) shielding current and associated magnetic and field energies. Any current flux change (synchronous or induced) will lead to dissipation and heating of the superconductor. Since the heat capacity at low temperatures is very small, a small amount of energy can cause large temperature drift until the superconductivity is completely broken and terminated. The strategy to avoid this instability is to reduce the available magnetic energy by forming filaments with diameters below 100μm. The common process of manufacturing such composite superconducting wire bodies is to stack individual filaments in large sizes and refine them by cold or/or hot methods to keep the regular shape and continuity of the filaments.
At least one of the steps required is thermal processing to obtain a good single metallurgical assembly of the composite, which can then deform uniformly. Hot - working processes usually involve extrusion. Sawing based conductors made into wires, cables and conductors of complex structures, including enhanced components and liquid nitrogen cooling channels, have become essential tools in the field of high magnetic fields. The design of conductors, such as their complexity and flow carrying capacity, depends greatly on specialized uses such as magnetic field levels, specifications, and geometric dimensions.
