Abstract body The second-generation high-temperature superconducting (2G-HTS) tapes are widely utilized in energy transmission, high-field magnets and so on. We have developed a novel ex-situ process to fabricate REBCO superconducting coated. This process consists of two main steps. The first step is to obtain a multicomponent metal film using multi-channel, multi-target DC magnetron co-sputtering. In the second step, the tape deposited with multicomponent metal film was subjected to sintering heat treatment to obtain a superconducting coating. In this paper, GdBCO superconducting films were produced using this novel process. By controlling temperature and oxygen partial pressure during the ex-situ sintering process, the transformation of multicomponent metal films to GdBCO has been investigated, and the evolution paths of their phase transitions have been identified. Furthermore, optimal sputtering parameters and sintering temperatures as well as oxygen partial pressure ranges for the growth of high quality superconducting coatings were determined. This new process we have developed shows great potential and significant advantages, especially in terms of reducing the cost of superconducting tape production and increasing the rate of superconducting tape manufacture. This study provides practical guidance and a reference for the development of a new technique to industrially fabricate REBCO superconducting tapes.

Figure 1. Surface morphology and XRD patterns of thin films after sintering. (a) SEM image of sintered at 820°C for 60 min. (b) XRD images of samples sintered at 820°C for different times.

Keywords: High-temperature superconductor, DC magnetron sputtering, Ex-situ sintering, Phase evolution