Superconducting materials have special physical properties such as zero resistance, diamagnetism, and macroscopic quantum effects. They have a wide range of applications. In the field of electrical engineering, the main applications of superconducting materials include superconducting cables, superconducting current limiters, superconducting magnetic levitation, medical magnetic resonance imaging, superconducting energy storage, and superconducting machines. At present, researchers from various countries focus on research and development and production of YBCO superconducting materials (also known as second-generation high-temperature superconducting materials), and consider them to be the main direction for the development of superconducting materials in the future.
According to survey and forecast data released by Strategies MRC in 2017, the global superconducting product market size was USD 820 million in 2015, and the market size will expand to USD 2.71 billion by 2022, with a compound annual growth rate (CAGR) of 18.6%. From the perspective of the value of the entire superconducting industry chain, superconducting materials can account for 40-50% of the cost of superconducting equipment. From the perspective of the profitability of the industrial chain, superconducting materials have the strongest profitability, with a gross profit margin of about 50%. At present, domestic superconducting materials are mainly imported from the United States and Japan, which are expensive and account for about 50% of the cost of superconducting applications.
Global pattern: the United States, Japan, and Europe lead, and China's practical application needs to be expanded
In recent years, developed countries represented by the United States, Japan, and the European Union have been actively promoting research on high-temperature superconducting materials and their applications, and have made many major breakthroughs. China's research progress in the field of superconducting materials has basically kept pace with international progress. Among them, the research in the fields of low temperature superconducting materials, superconducting electronics and superconducting engineering applications has reached or approached the international advanced level, but the research progress in practical applications still has a certain gap with developed countries.
Progress abroad: US and Japan lead, Europe and South Korea follow closely
The development of foreign superconducting materials is mainly led by the United States and Japan, followed by Europe and South Korea. In the field of BSCCO high-temperature superconducting wire, Japan's Sumitomo Electric Industries, Ltd. (SEI) has a great advantage, especially in the preparation of BSCCO-2223 wire, which is basically in a monopoly position. In the field of high-temperature superconducting wires in YBCO, Japan, the United States, and South Korea have basically competed with each other. In the field of high-temperature superconducting MgB2 found in 2001, Japan, the United States, and Europe are in a leading position. Representative companies include Columbus Superconductors SpA in Italy and HyperTech Corporation (HyperTech Research Inc.), and Hitachi, Ltd. of Japan.
Domestic progress: industrialization of the first generation, there is still a gap between the second generation and the international advanced level
At present, China has comprehensively broken through the practical low-temperature superconducting wire preparation technology, and has the ability to prepare thousands of practical MgB2 superconducting wires in batches. The gap between China's first-generation high-temperature superconducting tape (BSCCO-2223) and the international advanced level has been greatly reduced, and key technical indicators have basically reached the practical requirements, and have entered the stage of industrialization development. In the second generation of high-temperature superconducting tape (YBCO), the gap between China and the international advanced level has rapidly narrowed. Shanghai and Suzhou have prepared kilometer-level YBCO second-generation strips in the form of enterprises, and they have already been sold and used in a certain amount.
Development trends and suggestions
In terms of NbTi and Nb3Sn superconducting materials, China's share in the international market will gradually expand. Internationally renowned medical magnetic resonance imaging companies have gradually increased the purchase of superconducting materials in China. In addition, the superconducting magnets for scientific instruments in China are developing rapidly, and the demand for low-temperature superconducting wires will also increase rapidly.
With regard to MgB2 superconducting materials, with the development of open-type direct-cooling direct-cooled magnetic resonance imaging devices, the use of MgB2 wires will achieve greater development. R & D personnel will further improve the material's critical current and meet the market demand through further research to improve the material density and magnetic flux pinning ability.
In terms of BSCCO and YBCO superconducting materials, BSCCO-2223 superconducting wires will have further development in high-temperature cables and current limiters, but will gradually be replaced by YBCO second-generation high-temperature superconducting tapes with better performance. Low temperature and high magnetic field magnets based on BSCCO-2212 round wire will have further development. YBCO-based superconducting magnets will also gradually appear.
In terms of iron-based superconductivity, research on the practicality of iron-based superconducting materials will have further development. China will further develop kilometer-class iron-based superconducting wires. In view of the above, in terms of the research and application of practical superconducting materials in the future, the Tianjin Research Institute of the National New Materials Industry Development Strategy Advisory Committee has proposed 4 development suggestions.