Study of Cr segregation in martensitic stainless steels by XPS analysis

Cr martensitic stainless steels have excellent mechanical properties and good corrosion resistance. Due these reasons, they are possible candidates for structural applications in the future nuclear fusion reactors. The environmental in working conditions includes irradiation and/or heat treatments, which could cause the embrittlement of the steel due to Cr segregation. In the present work the chemical composition of the fracture surfaces of a 10.5 wt.% Cr martensitic stainless steel, previously broken in brittle or ductile field during the Charpy test, have been studied through X-ray photoelectron spectroscopy (XPS). The Cr segregation has been observed in both ductile and brittle quasi-cleavage fractures, so the aim of this study is to determine how this segregation depends on fracture temperature and to reveal the role that Cr plays in the embrittlement of the steel.