Magnetic field dependence of transport properties of YBa2Cu3O7-delta filmson hastelloy substrates with YSZ buffer layers

Biaxially aligned yttria stabilised zirconia (YSZ) buffer layers were depos ited on polycrystalline Hastelloy-C substrates using the inclined substrate deposition technique. In-plane aligned, c-axis oriented, YBa2Cu3O7-delta f ilms were then grown onto these buffer layers. Resistively determined irrev ersibility lines of these films are presented, as well as critical current densities which have been extracted from measurements of E - J characterist ics taken at 77.7 K for fields of up to 7 Tesla aligned either parallel or perpendicular to the ab-plane. Data are also presented showing the resistan ce as a function of the angle between the field and the c-axis. Strong pinn ing is observed both for fields parallel to the ab-plane (intrinsic pinning ), and for fields parallel to the c-axis; the latter being due to either tw in or grain boundaries.