Corrosion resistance of 13wt.% Cr martensitic stainless steels: Additively manufactured CX versus wrought Ni-containing AISI 420


The corrosion resistance of heat-treated additively manufactured (AM) precipitation hardening martensitic stainless steel (SS) CX and wrought components of AISI 420-SS with lower Ni content, were compared. The microstructure of heat-treated AM-CX comprised of a martensitic matrix and a few nano-scale particles, while the wrought AISI 420-SS contained approximately 8% of austenite and Cr-rich carbides in a martensitic matrix. Superior corrosion resistance was detected for the AM-CX part as compared to the AISI 420-SS ascribed to nearly absence of Cr-rich carbides and martensite-retained austenite interfaces in the AM-CX SS, while their presence in the AISI 420-SS destabilized the passive film.

Publication Title

Corrosion Science