A Process for Developing Long-Length Superconducting Joint Tube Assembly of Bi-2223 (10 wt% Ag)

A process for developing long-length joint tube assembly of Bi-2223 (10 wt% Ag) superconductor is presented. The process involves sintering of tubes fabricated from cold isostatic pressing of the partially preformed Bi-2223 (10 wt% Ag) superconducting powder. The joint was made between these sintered tubes. For making joints, sintered tubes were physically joined by connecting together on a common superconducting bush coated with a superconducting paste. Subsequently, the combination of the bush and the physically joined portion were sintered. The superconducting properties and phase identification/phase composition of the component tubes and of the joint portions have been investigated. The diametral fractural strength of the component tubes and of the joint portion was also evaluated. In the joint obtained according to this method, it is possible to retain the superconducting properties and the fractural strength of the joint high-temperature superconducting tubes. This technique is very useful for fabrication of very large sized superconducting apparatuses such as external magnetic shielding, transmission cables and electrical current leads, etc.