Abstract: | The effect of the superconducting transition on the flow stress in single and polycrystals of Pb-In and Pb-Sn alloys has been studied in the temperature range 1.8 K to Te. Unlike earlier efforts, these experiments involved investigation of the magnetic flux trapping. Two types of temperature dependences of the magnetic flux trapping, B0(T), were revealed. In Pb-1.9 at.% In and Pb-6 at.% Sn alloys (subjected to various thermal treatment), B0 monotonically rises with lowering temperature. In Pb-1.8, 3 at.% Sn single crystals the flux trapping arises at high strains (> 50%) and low temperatures (<2.5 K). In this case B0 magnitude depends on the strain rate. The difference in the B0(T) behaviour is associated with dissimilar flux pinnig by pinning centres. The date on B0(T) obtained give an insight into the two types of the Δσ(T) dependences; taking into account of the flux trapping allowed the Δσ values to be corrected, so that as a result, a single ΔσSN(T) curve was obtained for all the alloys and structures studied. |