Electromechanical Properties of Thin-Layer HTSC-2G Tape Wires at Helium Temperature and Tensile Stresses Above 1000 MPa

At present, HTSC-2G tape wires (hereinafter wires) are an uncontested basis for creating conductors for the magnetic system of a compact thermonuclear reactor. Since, according to calculations, the tangential mechanical stresses in the windings of its magnetic system can exceed 1000 MPa, the requirement for high electromechanical stability of the HTSC wire used comes first, which makes it possible to raise the constructive current density. In this work, comparative electromechanical test of HTSC-2G wires with different thicknesses of the superconducting layer, on a substrate made of AISI 310S stainless steel, at the temperature of liquid nitrogen and liquid helium were carried out. The factors leading to a decrease in the degradation of the critical current at high tensile stresses have been established. A new method for testing HTSC-2G wires at helium temperature and a simple method for preliminary assessment of their electromechanical properties at nitrogen temperature are proposed.