Enhancement of $J_{\mathrm{c}}$ Properties in Magnetic Fields of BaZrO3 Doped REBa2Cu3O6+δ Coated Conductors by a Newly Modified TFA-MOD Process

A modified heat-treatment procedure, which consisted of three steps, i.e., 1) calcination, 2) intermediate heat-treatment (IHT), and 3) crystallization, was developed for the metal organic deposition method using trifluoroacetates (TFA). BaZrO
₃
-doped Y
_0.77
Gd
_0.23
Ba
₂
Cu
₃
O
_6+δ
(YGdBCO) coated conductors fabricated by this modified procedure provided the minimum critical current density (J
_c
) value of 0.21 MA/cm
²
at 77 K in 3 T, which was as high as 2.1 times the value obtained by the conventional one, and a homogeneous dispersion of BaZrO
₃
nanoparticles with finer size in the matrix. Furthermore, the 1-D theoretical analysis of the reaction kinetics in the IHT process, considering diffusion and growth kinetics at the interface between the precursor layer and the calcined layer, was proposed, and the estimated reaction rate was compared with experimental ones.