Influence of the microstructure on the corrosion behaviour of low-carbon martensitic stainless steel after tempering treatment

• Published in: Corrosion science Vol. 85; pp. 42 - 51
• Main Authors: Vignal, V., Ringeval, S., Thiébaut, S., Tabalaiev, K., Dessolin, C., Heintz, O., Herbst, F., Chassagnon, R.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-08-2014; Elsevier
• Subjects: A. Stainless steel; Applied sciences; C. Pitting corrosion; Corrosion; Corrosion environments; Exact sciences and technology; Metals. Metallurgy; C. Pitting corrosion; A. Stainless steel; Martensitic stainless steel; Pitting corrosion; Heat treatment; Martensitic steel; Tempering; Low carbon steel; Stainless steel; Carbon steel; Microstructure
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2014.03.036

•Microstructure of grade X4CrNiMo16.5.1 stainless steel down to the nanoscale.•Influence of microstructure on the properties of the native passive film.•Influence of microstructure on pitting of grade X4CrNiMo16.5.1 stainless steel.
The microstructure of grade X4CrNiMo16.5.1 stainless steel was studied at different scales. The chemical composition of the native passive film formed on the different phases was then determined at the microscale. The degree of homogeneity of the native passive film is discussed. Subsequently, the susceptibility to pitting corrosion of X4CrNiMo16.5.1 was quantified using the electrochemical microcell technique. The nature of precursor sites and the morphology of pits were investigated by combining scanning electron microscopy with Electron BackScatter Diffraction and potentiostatic pulse tests. The role of the microstructure and the cold-worked layer generated by polishing in pitting is discussed.