Tensile and fatigue behavior of a Pb-Sn-Sb alloy investigated via small-scale in-situ mechanical testing in SEM

Pb-Sn-Sb alloys (E-alloy) are commonly used in subsea power cable sheathing. Due to the relatively low melting temperature, i.e. around 600 K, this type of alloy is prone to experience microstructural time-dependent evolution such as recovery, relaxation, recrystallization and creep deformation even at room temperature, in contrast to other conventional materials for which involve these mechanisms are activated only at high temperatures. To better understand the deformation mechanisms of Pb-Sn-Sb alloys, small-scale in-situ mechanical testing inside a scanning electron microscope (SEM) has been conducted under both monotonic loading and cyclic loading conditions. Thanks to the in-situ imaging technique, the deformation behavior as well as the damage mechanisms were revealed with high resolution. The possible deformation mechanisms, including the creep behavior, has been discussed and the results can provide necessary input to damage calculations and modelling work of the studied alloy system used for cable sheathing.