Development of a methodology for measuring the evolution of duplex stainless-steel low-temperature plasma nitrided phases expansion using confocal laser scanning microscopy

Samples of duplex stainless steel SAF 2507 were low-temperature plasma nitrided to characterize separately, on the surface, behavior its ferrite and austenite phases in relation two competing processes, that is, one caused by enrichment nitrogen, resulting possible expansion, other removal superficial atoms via sputtering, which may lead retraction studied phases. Since these have different compositions crystalline structures, diffusivity solubility nitrogen them are dependent, a response for each type phase can be expected. In this article, an innovative methodology has been developed quantify clarify effects predominant course nitriding The results indicate expansion prevails over sputtering.