Optimization of Transport Critical Currents at 4.2 K - 20 K at Magnetic Fields Up to 31 T for MOCVD REBCO Conductors With Variable Zr and Growth Conditions

The critical current, Ic, of REBCO full-width 4 mm short samples made by metal-organic chemical vapor deposition (MOCVD), optimized for high-field applications, were measured at magnetic fields perpendicular to sample plane up to 31.2 T in resistive magnets and temperature range 4.2\K-55 K. Dependencies of Ic, critical current density (Jc), and pinning force density (Fp) on Zr doping and REBCO growth conditions were studied. SEM images of cross-section and top view of the REBCO layers for tapes with 15%, 20%, and 25% Zr doping show dense REBCO layers without secondary phases or porosity. REBCO tapes with 20% and 25% Zr doping perform better in transport Ic(T,μoH) tests at 20 K and 20 T conditions than tapes with lower Zr doping and can be promising candidates for applications focusing on magnetic plasma confinement.