Interaction of transport current and transient external field in composite conductors

Investigations of transient field losses in superconducting composites carrying transport current are presented. The magnetization and terminal voltage of a variety of composites have been measured as a function of transport current and external field. The losses are analyzed as a sum of magnetization losses and those due to dynamic resistivity. Results are presented for slowly changing external fields where the magnetization losses are purely hysteretic and for higher
\dot{B}
where coupling losses are important.