Abstract
The role of prior austenite grain size (PAGS) on the passive layer properties of martensitic steels is studied. Electron backscatter diffraction analysis shows that PAGS between 5 and 66 µm were obtained after applying different heat treatments. The barrier properties of passive film deteriorate with grain refinement up to 28 µm, attributed to increased donor density and a decrease in the fraction of γ-Fe2O3 in passive films. However, the further refinement of PAGS to 5 µm leads to improvement in the barrier properties due to the changes within the martensite structure. This improvement stems from the increase in γ-Fe2O3 fraction.
Original language | English |
---|---|
Article number | 292 |
Number of pages | 13 |
Journal | Metals |
Volume | 12 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2022 |
Keywords
- martensitic steel
- grain-size
- passivity
- electrochemical impedance spectroscopy
- Mott-Schottky analysis
- X-ray photoelectron spectroscopy