$J_{\rm c}-B$ Properties of ${\rm YBa}_{2}{\rm Cu}_{3}{\rm O}_{7}$ Films Prepared on

The Cu substrates have the advantages of no ferromagnetic contribution to hysteretic AC losses, and low cost compared to Ni substrates. We investigated the J_c-B properties of YBCO films deposited on the cube-textured Cu tapes with intervening buffer layers. A protective Ni overlayer was added on top of the cube-textured Cu tape by electroplating to reduce the oxidation rate of the Cu substrate. The YBCO films prepared on the CeO₂/YSZ/CeO₂ buffered Ni-electroplated Cu tapes revealed the transport J_c exceeding 3.6 MA/cm² at 77 K in a self-field. We also confirmed that our Ni-electroplated Cu tape lost its ferromagnetism after 700degC times 1 hour heat treatment.