Радиационная обработка краев трещины сверхпроводящего слоя при реставрации ВТСП-ленты

Numerically, within the framework of the critical state model, the density of superconducting currents in a second-generation HTSC tape based on GdBa2Cu3O7-x is determined. It is shown that during the restoration of the transverse crack of the superconducting layer by shunting the crack with a piece of defect-free tape, the critical current of the restored area decreases by ~ 8%. It is shown that preliminary irradiation of the crack edges with ions of hydrogen, helium, neon, and oxygen makes it possible to restore the initial value of the critical current. The calculation of the effect of radiation on a superconducting tape was carried out using the SRIM software package

Физические принципы создания магнитолевитационных систем на основе высокотемпературных сверхпроводящих композитов второго поколения (Обзор)

An overview of experimental and theoretical studies of the characteristics of maglev systems using high-temperature superconductors (HTSC) is presented. Materials used in maglev technologies, namely bulk superconductors and HTSC tape composites, are considered. The main experimental data obtained on both bulk and tape superconductors assembled in stacks of various configurations are demonstrated. The factors influencing the magneto-force characteristics are analyzed: geometric parameters, the influence of external alternating magnetic fields, temperatures, relaxation phenomena. A significant part of the review is devoted to the description of various methods for calculating maglev systems, including those based on stacks of HTSC composites. The features of thermal processes in maglev systems with cryocooler and nitrogen cooling are considered. General recommendations for the creation of optimal maglev systems based on tape HTSC composites are given.

Влияние времени нарастания напряжения на переходные процессы при токовой перегрузке в стабилизированных ВТСП-проводах второго поколения

The effect of spontaneous reverse transition of the stable HTSC tape from the normal to the resistive state with rapid input voltage and current overload at alternating current is detected. For the first time it is established that during the occurrence of this effect and at the thickness of the stabilizer above 13 µm, the main heat releases occur in the copper stabilizer and are effectively discharged into the refrigerant, which significantly reduces the heating of the HTSC layer. In this case, the resistance of the secondary resistive state decreases and the time of its existence increases. These data make it possible to use the detected effect to increase the time of current limitation and reliability of HTSC current limiters.