Počet záznamů: 1  

Oxidation of Inconel 625 superalloy upon treatment with oxygen or hydrogen plasma at high temperature

  1. 1. 0487615 - UFP-V 2018 RIV NL eng J - Článek v odborném periodiku
    Vesel, A. - Drenik, A. - Elersic, K. - Mozetič, M. - Kovač, J. - Gyergyek, T. - Stöckel, Jan - Varju, Jozef - Pánek, Radomír - Balat-Pichelin, M.
    Oxidation of Inconel 625 superalloy upon treatment with oxygen or hydrogen plasma at high temperature.
    Applied Surface Science. Roč. 305, June (2014), s. 674-682 ISSN 0169-4332
    Grant CEP: GA MŠk(CZ) LM2011021
    Institucionální podpora: RVO:61389021
    Klíčová slova: Inconel * Oxidation * High temperature * Oxygen plasma * Hydrogen plasma
    Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
    Obor OECD: Fluids and plasma physics (including surface physics)
    Impakt faktor: 2.711, rok: 2014

    Initial stages of Inconel 625 superalloy (Ni60Cr30Mo10Ni4Nb1) oxidation upon short treatment with gaseous plasma at different temperatures up to about 1600 K were studied. Samples were treated for different periods up to a minute by oxygen or hydrogen plasma created with a microwave discharge in the standing-wave mode at a pressure of 40 Pa and a power 500W. Simultaneous heating of the samples was realized by focusing concentrated solar radiation from a 5 kW solar furnace directly onto the samples. The morphological changes upon treatment were monitored using scanning electron microscopy, compositional depth profiling was performed using Auger electron spectroscopy, while structural changes were determined by X-ray diffraction. The treatment in oxygen plasma caused formation of metal oxide clusters of three dimensional crystallites initially rich in nickel oxide with the increasing chromium oxide content as the temperature was increasing. At about 1100K iron and niobium oxides prevailed on the surface causing a drop of the material emissivity at 5 pm. Simultaneously the NiCr2O4 compound started growing at the interface between the oxide film and bulk alloy and the compound persisted up to temperatures close to the Inconel melting point. Intensive migration of minority alloying elements such as Fe and Ti was observed at 1600K forming mixed surface oxides of sub-micrometer dimensions. The treatment in hydrogen plasma with small admixture of water vapor did not cause much modification unless the temperature was close to the melting point. At such conditions aluminum segregated on the surface and formed well-defined Al2O3 crystals
    Trvalý link: http://hdl.handle.net/11104/0282266