Development of a superconducting joint between a GdBa₂Cu₃O7-δ-coated conductor and YBa₂Cu₃O7−δbulk: towards a superconducting joint between RE (Rare Earth) Ba₂Cu₃O7−δ-coated conductors

We have started to develop a superconducting bridge joint between two GdBa 2 Cu 3 O 7− δ (Gd123)-coated conductors, where both conductors are placed in an end-to-end arrangement on the surface of a melt-textured YBCO (including Y 2 BaCuO 5 and YBa 2 Cu 3 O 7− δ ) bulk, which acts as a superconducting medium between the coated conductors. As a first step in the development, one half of the bridge joint assembly was modeled and investigated. Experimental results achieved are as follows: (a) the higher-melting-temperature textured Gd123-coated conductor acts as a seed for the melt texture of the YBa 2 Cu 3 O 7− δ (Y123) bulk, and (b) the superconducting phase continues across the Y123/Gd123 boundary. The critical current of the joint model is 10 A, which is about 10% of the original Gd123-coated conductor, at 77 K in a self-magnetic field. These results are considered to be extensible to the superconducting bridge joint between the Gd123-coated conductors.