Chromium Vaporisation from AISI 441 Stainless Steel Oxidised in Humidified Oxygen

• DOI: 10.1007/s11085-013-9379-x
• Publication Date: 2013-02-20T10:56:17Z
• Authors: Wichitra Wongpromrat; Harit Thaikan; Walairat Chandra-...; Somrerk Chandra-a...
• Keywords: 02 engineering and technology; 0210 nano-technology; 7. Clean energy

Chromium vaporisation from chromia-forming alloys when exposed to high temperatures can deteriorate the protective property of oxide scale. This problem affects the lifetime of solid oxide fuel cells and solid oxide electrolysers using chromia-forming alloys as interconnectors. In this work, AISI 441, a commercial grade stainless steel which chromium vaporisation investigation has not been reported so far, was chosen for study. Chromium vaporisation rates of bare AISI 441 and AISI 430 and AISI 441 and AISI 430 coated with Mn–Co spinel by electroplating method were measured in an atmosphere of 5 % H2O in O2 over the temperature range of 650–900 °C with the linear velocity of the humidified oxygen stream varied in the range of 0.8–3.0 cm s−1. For uncoated samples, AISI 441 showed a lower chromium vaporisation rate in comparison with that of AISI 430. Mn–Co spinel coating could reduce the chromium vaporisation rate from AISI 430 surface. However, on the contrary, the Mn–Co spinel coating could not only fail to suppress the chromium vaporisation, but it also promoted the chromium vaporisation from AISI 441 surface by 2 times.