Abstract
The critical current density of lead foils carrying a transport current parallel to the layers in laminar structure has been measured by observation of flux domain motion. The pinning force density Fp is estimated by using the critical state model. The Fp obeys the scaling law; Fp=Hc2(T)h(1−h)2(Sp⁄d+Bp), where Hc(T), h and d are the critical magnetic field, the reduced magnetic field and the specimen thickness, respectively; Sp, Bp are material constants. The temperature and reduced magnetic field dependences of Fp are discussed in comparison with a model in which the interaction between dislocation lines and superconducting-normal domain walls is assumed.
