Electromagnetic Properties of $(\hbox {Gd}, \hbox {Y}) \hbox {Ba}_{2}\hbox {Cu}_{3}\hbox {O}_{\rm x}$ Superconducting Tapes With High Levels of Zr Addition

The dependence of the critical current density (J_c) on the orientation of applied magnetic fields was studied in Zr-doped ( Gd, Y)Ba₂Cu₃Ox tapes fabricated by metal organic chemical vapor deposition. The in-field performance of J_c of (Gd, Y)Ba₂Cu₃Ox tapes with Zr-doping levels of 7.5-30 at.% was investigated up to 5 T over a temperature range of 40-77 K. The highest critical currents (I_c) at H ||c and the highest values of minimum I_c in angular dependence measurements were achieved in the tapes with 20% Zr doping over a broad range of temperature and magnetic field conditions measured. The electromagnetic properties have been related to the changes in BaZrO₃ content and microstructure.