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)Ba
₂
Cu
₃
O
x
tapes fabricated by metal organic chemical vapor deposition. The in-field performance of
J
_c
of (Gd, Y)Ba
₂
Cu
₃
O
x
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 BaZrO
₃
content and microstructure.