Pulse current treatment of SUS304 stainless steel foils at different rolling deformation levels to achieve superior microstructural properties

To overcome the severe work hardening, inhomogeneous microstructure, and poor plastic deformation capacity of stainless steel foils after rolling, this study applied high-frequency pulse current treatment to rolled stainless steel foils, and investigated the influence of pulse current treatment on foils at different rolling deformation levels. Heat treatment experiments with identical temperatures and holding times were designed to explore the mechanism of non-thermal effects on the microstructural properties of stainless steel foils. The results showed that the non-thermal effects generated by the pulse current were characterized by an increase in the driving force for recrystallization, a reduction in the nucleation barrier, and a change in the nucleation mechanism, thereby enabling recrystallization to occur at relatively low temperatures. Specifically, the sample with 30% rolling deformation underwent partial recrystallization at 630°C, while the sample with 50% rolling deformation underwent complete recrystallization at 710°C, accompanied by grain morphology reconstruction, disappearance of texture aggregation, and a significant enhancement in plastic deformation capacity. These findings demonstrated that pulse current treatment technology, as a novel heat treatment process, showed significant potential in efficiently restoring the microstructural properties of the stainless steel strips after rolling.