Deformation analysis for the superconductor-silver interface in the Bi-2223/Ag tape rolling process

Abstract

Abstract. Analytical model of interface deformation behavior during rolling process was established to investigate the principle of sausaging formation, and formula involving the geometric parameters and physical properties of silver layer was derived on the basis of energy approach. Moreover, the curvature difference of interface before and after deformation was defined as evaluation factor for the interface forming quality. Numerical model of Bi-2223/Ag high temperature superconducting wires during rolling was proposed, and the effect of process parameters such as inner tube material, roller diameter and friction coefficient on the deformation behaviors of the interface in Bi-2223/Ag wire was analyzed. The results suggest that inner sheath material with high strength contributes to a better silver-super interface. Simultaneously, larger roller and small friction coefficient weaken the interface instability and obtain the final tape with high critical current density. In addition, the numerical results verify the accuracy of the theoretical derivation.

Research on the deformation law for flat rolling of a core filled tube based on the slab method

“…Lu et al [13] simulated the influences of initial shape on the homogeneity and density of the core material of a HTS system during the rolling process and verified the simulation by conducting experiments. Lu [14] studied the cause and influencing factors of the sausage effect (the thickness of the powder changes along with the coordinate in the length direction) for multiple HTS tapes. The rolling process was simulated using the finite element method, and the influences of roll diameter, coefficient of friction, and yield strength on the sausage effect were analyzed.…”