The microstructure of the Sanicro 25 steel after steam oxidation studied by advanced electron microscopy and spectroscopy methods

• Autorzy: Rutkowski B. , Gil A. , Ratuszek W. , Woźniak B. , Czyrska-Filemonowicz A.

Identyfikatory

DOI

10.15199/28.2016.5.3

Warianty tytułu

PL

Mikrostruktura stali Sanicro 25 po utlenianiu w parze wodnej badana za pomocą zaawansowanych metod mikroskopowych i spektroskopowych

• Języki publikacji: EN

Abstrakty

EN

Increase of the coal fired power plants efficiency is inseparable with an increase of the steam conditions. Currently used 9÷12% Cr steels are not able to withstand pressure of 30 MPa at 700°C for a long time due to their microstructure instability leading to fast damage. Development of new Fe-based materials able to work under advanced ultra-supercritical (A-USC) conditions for a long time is the key of importance. Present paper deals with a microstructure of the prospective, 22% Cr austenitic steel, Sanicro 25, heat treated or oxidized in water vapour at 700°C. Detailed characterization of the steel was performed using X-ray diffractometry as well as scanning and transmission electron microscopy techniques. Investigation led to establish the effect of temperature and water vapour environment on the microstructure stability of this modern austenitic steel. The results showed that the microstructure of the aged steel consists of M23C6 and Laves phase precipitated on the grain boundaries as well as ε-Cu, NbN, M23C6 and Z-phase precipitated within the grains. After oxidation at 700°C up to 5000 h in water vapour, Sanicro 25 developed a thin protective oxide scale at the surface, consisting mainly of Cr2O3 plates, characteristic for steels oxidation in vapour.

PL

W pracy przedstawiono wyniki badań stabilności mikrostruktury stali Sanicro 25 (22Cr25NiWCoCu) po starzeniu w temperaturze 700°C w czasie krótszym niż 1000 h oraz po utlenianiu w atmosferze pary wodnej w tej samej temperaturze do 5000 h. Szczególną uwagę poświęcono mikrostrukturze zgorzeliny wykształconej na powierzchni stali podczas utleniania w temperaturze 700°C oraz zmianom mikrostruktury materiału rodzimego.

Słowa kluczowe

EN

Sanicro 25; TEM; oxidation; water vapour; A-USC

PL

Sanicro 25; utlenianie; para wodna; A-USC

• Wydawca: Wydawnictwo SIGMA-NOT
• Czasopismo: Inżynieria Materiałowa
• Rocznik: 2016
• Tom: Vol. 37, nr 5
• Strony: 223--227
• Opis fizyczny: Bibliogr. 15 poz., fig., tab.

Twórcy

autor

Rutkowski B.

• International Centre of Electron Microscopy for Materials Science and Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Kraków, Poland

autor

Gil A.

• Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Kraków, Poland

autor

Ratuszek W.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Kraków, Poland

autor

Woźniak B.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Kraków, Poland

autor

Czyrska-Filemonowicz A.

• International Centre of Electron Microscopy for Materials Science and Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Kraków, Poland

Bibliografia

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• [2] WB 555, Warmfester austenitischer Stahl, Sanicro ® 25, VdTÜV Merkblätter. (2008).
• [3] Rutkowski B., Gil A., Czyrska-Filemonowicz A.: Microstructure and chemical composition of the oxide scale formed on the Sanicro 25 steel tubes after fireside corrosion. Corros. Sci. 102 (2016) 373÷383 doi:10.1016/j.corsci.2015.10.030.
• [4] Intiso L., Johansson L. G., Canovic S., Bellini S., Svensson J. E., Halvarsson M.: Oxidation behaviour of Sanicro 25 (42Fe22Cr25NiWCuNbN) in O2/H2O mixture at 600°C. Oxid. Met. 77 (2012) 209÷235 doi:10.1007/ s11085-011-9281-3.
• [5] Rautio R., Bruce S.: Sandvik Sanicro 25, a new material for ultra supercritical coal fired boilers. Proc. 4th Int. Conference on Advances in Materials Technology for Fossil Power Plants, 25÷28.10.2004, Hilton Head Island, South Carolina, USA, R. Viswanathan et al. (eds) (2005) 274÷281.
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• [11] Rana R., Bleck W., Singh S. B., Mohanty O. N.: Development of high strength interstitial free steel by copper precipitation hardening. Mater. Lett. 61 (2007) 2919÷2922 doi:10.1016/j.matlet.2006.10.037.
• [12] Tan S., Wang Z.-H., Cheng S., Liu Z., Han J., Fu W.: Effect of Cu content on aging precipitation behaviours of Cu-rich phase in Fe–Cr–Ni alloy. J. Iron Steel Res. Int. 17 (2010) 63÷68 doi:10.1016/S1006-706X(10)60101- X.
• [13] Ren L., Nan L., Yang K.: Study of copper precipitation behaviour in a Cu-bearing austenitic antibacterial stainless steel. Mater. Des. 32 (2011) 2374÷2379 doi:10.1016/j.matdes.2010.11.030.
• [14] Rutkowski B., Galanis A. S., Gil A., Czyrska-Filemonowicz A.: A novel approach to the characterization of thin oxide layers. Mater. Lett. 173 (2016) 235÷238 doi:10.1016/j.matlet.2016.02.104.
• [15] Zurek J., Yang S.-M., Lin D.-Y., Hüttel T., Singheiser L., Quadakkers W. J.: Microstructural stability and oxidation behaviour of Sanicro 25 during long-term steam exposure in the temperature range 600÷750°C. Mater. Corros. 66 (2015) 315÷327 doi:10.1002/maco.201407901.

Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę.