Isothermal oxidation behavior of MCrAlY bond coats after laser microtexturing
Monday, May 22, 2023: 11:50 AM
301A (Quebec City Convention Centre)
Mr. Tomasz Kiełczawa
,
Wrocław University of Science and Technology, Wrocław, Poland
Dr. Pawel Sokolowski
,
Wrocław University of Science and Technology, Wrocław, Poland, Wrocław University of Science and Technology, Wrocław, Poland
Dr. Hanna Myalska-Głowacka
,
Silesian University of Technology, Gliwice, Poland, Université de Limoges, Limoges, France
Prof. Grzegorz Moskal
,
Silesian University of Technology, Gliwice, Poland
Dr. Alberto Ion
,
Université de Limoges, Limoges, France, Politehnica University of Bucharest, Bucharest, Romania
Dr. Alain Denoirjean
,
Université de Limoges, Limoges, France
The performance and applicability of Thermal Barrier Coatings (TBCs) depend strongly on the top coat and bond coat interface integrity. The interlayer in TBC systems is often processed prior to top coat spraying to tailor its material properties or surface topography. However, commonly used bond coat spraying and post-processing may significantly influence the thermally grown oxides (TGOs) build-up which is crucial in terms of enhancing TBC lifetime.
In this work, NiCrAlY bond coats were sprayed by means of Atmospheric Plasma Spraying and Cold Spraying processes. Additionally, free-standing and oxide-free NiCrAlY sinters were produced by hot-isostatic pressing in Degussa press, as a reference sample. All produced samples were subjected to similar, topography-oriented bond coat post-processing, including: grinding, sandblasting, and laser microtexturing. Then, the samples were exposed to isothermal oxidation conditions under various oxidation times. The preliminary assessment of the oxidation mechanisms and oxides distribution was done by Light Microscopy and Scanning Electron Microscopy (SEM/EDS). In order to analyze the oxidation products, aluminum loss during oxidation and oxides morphology the X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Electron Back-scattered Diffraction (EBSD) methods were used.
