Abstract

By oxidation weight gain method, four groups of Fe-based superalloys with different content of chromium, aluminium and silicon were tested at 1 200 °C for 500 hours. According to the oxidation weight gains, the oxidation kinetic curves were plotted, and the equations were regressed by least square method and non-linear curve fitting. The effects of different scale compositions on the morphology and oxidation kinetic law were studied further by analysis of X-ray diffraction (XRD) and scanning electron microscope (SEM). It is found that the compounded scale is composed of Cr2O3, Al2O3, SiO2 and FeCr2O4, with compact structure and fine grains, possessing complete oxidation resistance at 1 200 °C, and the oxidation kinetic curve follows the power function of y=ax b (a>0, 0<b<1). When the compounded scale lacks Al2O3 or SiO2, it becomes weak in oxidation resistance, but the oxidation kinetic curve still follows the power function with bigger parameter b. When Cr2O3 is absent, the kinetic curve shows two parts: the slow adding of oxidation weight gains at the beginning and the ascending line in the end. Such scale loses oxidation resistance completely.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.