| Abstract Scope |
Stainless steels for PEMFC bipolar plates require excellent corrosion resistance and electrical conductivity. While low-temperature carburization (LTC) is known to enhance the corrosion resistance and mechanical properties of conventional stainless steels, its effects in additively manufactured (AM) 316L are not fully understood. This study explores the impact of LTC on AM 316L, focusing on passive film's chemical/electrochemical properties and mechanical strength. The passive film exhibited a significantly increased passive current and higher breakdown potential, associated with carbon-improved conductivity and induced transpassive stability, respectively. Tensile testing of micro-specimens lifted from the carburized layer revealed notable gains in both strength and ductility over untreated material. Sub-atomic spectroscopic analysis confirmed changes in the electronic structure of lattice iron, linked to compressive stress and altered bond strength. Overall, these findings highlight that low-temperature carburization can simultaneously boost both the electrochemical and mechanical performance of AM 316L, advancing the development of high-performance, sustainable stainless steel bipolar plates. |
