Japan developed a high-temperature superconducting wire

It is reported that Sumitomo Electric Industries Co., Ltd. has successfully developed a ceramic type high-temperature superconducting wire, which can pass 350 times the current density of the copper wire when the resistance is zero, which is the highest in the world. The use of such wires for making cables, including construction costs such as laying costs, can save costs by 10% to 20% compared to current ordinary cables.
The new wire is a ceramic high-temperature superconductor made of yttrium, lead, antimony, bismuth, oxygen, etc. Its width is 3.8 mm and its thickness is 0.24 mm. The length that can be processed now reaches 500 meters, which is sufficient for mass production. This wire was immersed in liquid nitrogen and cooled to -196°C below zero to maintain its superconducting state. Its maximum current density, the critical current density, reached 35,000 amps/cm2. This density reached 1.4 times the critical current density recorded by the company and 350 times that of the copper wire. In the past, the company had also produced 30,000 amps of ceramic superconducting wire materials, but the lengths that can be machined are very short and it cannot be practically used. The wire rods with a length of 500 meters were machined this time, and the full-length quality was good for the first time. If copper cables are used, the current that can pass through each copper wire is limited, so it must be bundled and laid in a pipe with a diameter of 3 meters. If this type of high-temperature superconducting material is used, the number can be less than 1% of the copper wire, including the cooling layer, and it can be buried in a pipe with a diameter of 15 cm. Although the superconducting wire is more expensive than the copper wire, its power loss is only 1/3 of the copper wire, and the laying is simple. Therefore, the overall construction cost can be reduced by 10% to 20% compared with the copper wire cable.
According to estimates of relevant experts, the market size of high-temperature superconducting materials is expected to reach 500 billion yen by 2010. Superconducting wire can be used not only on magnetic levitation trains and electromagnetically propelled ships, but also superconducting cables are a promising area. In order to realize the practical application of superconducting cables in 2010, Sumitomo Electric Industries Co., Ltd., Japan's Toyo Electric Co., Ltd., and Japan Electric Power Central Research Institute will begin to use the superconducting wire with a lower critical current density than the developed high-temperature superconducting wire in June. Power-on test, strive to use two years to find out problems that hinder the practical application, and further improve the wire rod.