Recently, we can witness the increase of genuinely commercial applications of High-temperature Superconducting(HTS) devices, one of the remarkable examples of which is a 23-kV superconducting cable recently energized in Korea. In addition, several start-up companies declared their plan for HTS fusion reactors with the aim of commercially generating electricity as early as 2030, which attract investments from venture capitals. These mean that 2G HTS tapes anticipate large markets in grid applications and fusion reactors, to say the least.

SuNAM developed RCE-DR(Reactive Co-Evaporation – Deposition and Reaction) process and production facilities for coated conductor(CC) manufacturing, capable of producing 400 km/year(4 mm equivalent) of tapes with critical current higher than 800 A/12mm-width. Based on this, we have been actively engaging in a couple of commercial projects, as well as many research projects by providing CC tapes.

To meet the growing demands, we recently set up a new RCE-DR system with a 100 kW electron-gun.  Using the new system, we evaporated other materials than current Gd, Ba, and Cu to be incorporated as artificial pinning centers which were difficult to be achieved in the old system with only a 30 kW power.  We also mix rare earths to see the effects on Re₂O₃ formation.  Critical current of new tapes increased at least by two times compared to our products at low temperatures(down to 20 K) and medium magnetic fields(up to 4 T).  Measurements at higher fields are on the way, as well as thicker tape process development for J_E enhancements.

Our activities on magnet development and stacked tape for large current conductors are presented.

Acknowledgements
This work was supported by Nano-Convergence Foundation funded by the Ministry of Science and ICT(MSIT, Korea) & the Ministry of Trade, Industry and Energy(MOTIE, Korea) [Project Number: R201902010]

Keywords: Coated Conductor, Critical Current, High Magnetic Field, Superconducting Cable