TY - JOUR
T1 - Correlative EBSD and SKPFM characterisation of microstructure development to assist determination of corrosion propensity in grade 2205 duplex stainless steel
AU - Örnek, C.
AU - Engelberg, D. L.
N1 - Publisher Copyright:
© 2015, The Author(s).
PY - 2016/2/1
Y1 - 2016/2/1
N2 - Correlative electron backscatter diffraction (EBSD) and scanning Kelvin probe force microscopy (SKPFM) analysis has been carried out to characterise microstructure development and associated corrosion behaviour of as-received and 750 °C heat-treated grade 2205 duplex stainless steel. High-resolution EBSD analysis revealed the presence of σ- and χ-phase, secondary austenite, Cr2N, and CrN after ageing treatment. SKPFM Volta potential measurements confirmed the formation of discrete reactive sites, indicating local corrosion propensity in the microstructure. Cr2N, σ-phase, and inter-granular χ-phase had the largest net cathodic activity, followed by CrN and intra-granular χ-phase showing medium electrochemical activity, with ferrite and austenite (including secondary austenite) showing net anodic activity. Corrosion screening confirmed selective corrosion of ferrite in the as-received and 750 °C-aged conditions with the corrosion propensity of secondary phases staying in-line with SKPFM observations. Stress corrosion micro-cracks were also observed and are discussed in light of microstructure corrosion propensity.
AB - Correlative electron backscatter diffraction (EBSD) and scanning Kelvin probe force microscopy (SKPFM) analysis has been carried out to characterise microstructure development and associated corrosion behaviour of as-received and 750 °C heat-treated grade 2205 duplex stainless steel. High-resolution EBSD analysis revealed the presence of σ- and χ-phase, secondary austenite, Cr2N, and CrN after ageing treatment. SKPFM Volta potential measurements confirmed the formation of discrete reactive sites, indicating local corrosion propensity in the microstructure. Cr2N, σ-phase, and inter-granular χ-phase had the largest net cathodic activity, followed by CrN and intra-granular χ-phase showing medium electrochemical activity, with ferrite and austenite (including secondary austenite) showing net anodic activity. Corrosion screening confirmed selective corrosion of ferrite in the as-received and 750 °C-aged conditions with the corrosion propensity of secondary phases staying in-line with SKPFM observations. Stress corrosion micro-cracks were also observed and are discussed in light of microstructure corrosion propensity.
UR - https://www.scopus.com/pages/publications/84953363001
U2 - 10.1007/s10853-015-9501-3
DO - 10.1007/s10853-015-9501-3
M3 - Article
AN - SCOPUS:84953363001
SN - 0022-2461
VL - 51
SP - 1931
EP - 1948
JO - Journal of Materials Science
JF - Journal of Materials Science
IS - 4
ER -