The effect of dislocation tangles on superconducting properties

The microstructure of deformed Mo-34 a/o Re alloys has been correlated with normal state resistivity and superconducting properties. A model based on the dislocation cell structure is able to account for the variation of normal state resistivity, upper and lower critical fields, and magnetic hysteresis, in the superconducting state. The superconducting properties are shown to be dominated by the presence of high-resistivity cell walls. In particular the movement of quantized flux vortices is hampered by an interaction with the interfaces of this cell structure. Calculated parameters are in reasonable agreement with observed values.