Atom probe tomography of thermally grown oxide scale on FeCrAl

Oxidation has been considered as one of the principal disruptive factors in thermal barrier coating systems during service. So, oxidation behavior of thermal barrier coating (TBC) systems with nanostructured and microstructured YSZ coatings was investigated at1000∘Cfor 24 h, 48 h, and 120 h. Air plasma sprayed nano-YSZ coating exhibited a trimodal structure. Microstructural characterization also demonstrated an improved thermally grown oxide scale containing lower spinels in nano-TBC system after 120 h of oxidation. This phenomenon is mainly related to the unique structure of the nano-YSZ coating, which acted as a strong barrier for oxygen diffusion into the TBC system at elevated temperatures. Nearly continues but thinner Al2O3layer formation at the NiCrAlY/nano-YSZ interface was seen, due to lower oxygen infiltration into the system. Under this condition, spinels formation and growth on the Al2O3oxide scale were diminished in nano-TBC system compared to normal TBC system.

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A Correlative Atom-Probe Tomography and Transmission Electron Microscope Study of a Thermally Grown Oxide on a Commercial Nickel-Based Superalloy, René N'5 Y+®

Microscopy and Microanalysis ◽

10.1017/s143192761300682x ◽

2013 ◽

Vol 19 (S2) ◽

pp. 966-967

Author(s):

S.-I. Baik ◽

X. Yin ◽

D.N. Seidman

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Atom Probe Tomography ◽

Microscope Study ◽

Electron Microscope Study ◽

Atom Probe ◽

Thermally Grown Oxide ◽

Nickel Based Superalloy ◽

Transmission Electron ◽

Transmission Electron Microscope Study

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

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Thermally grown oxide formation on Ni2Al3 aluminide coating: The effect of nanocrystalline nickel film on oxide scale adhesion

Vacuum ◽

10.1016/j.vacuum.2021.110843 ◽

2021 ◽

pp. 110843

Author(s):

A. Khan ◽

A. Ullah ◽

Ihsan Ullah ◽

S.H. Zhang ◽

G.S. Song

Keyword(s):

Oxide Scale ◽

Aluminide Coating ◽

Thermally Grown Oxide ◽

Nickel Film ◽

Oxide Formation ◽

Nanocrystalline Nickel ◽

Scale Adhesion ◽

Thermally Grown

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Correlative Atom Probe Tomography and Transmission Electron Microscopy Analysis of Grain Boundaries in Thermally Grown Alumina Scale

Microscopy and Microanalysis ◽

10.1017/s143192761801557x ◽

2019 ◽

Vol 25 (1) ◽

pp. 11-20 ◽

Cited By ~ 4

Author(s):

Ivan Povstugar ◽

Juliane Weber ◽

Dmitry Naumenko ◽

Taihong Huang ◽

Martina Klinkenberg ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Grain Boundaries ◽

Atom Probe Tomography ◽

Alumina Scale ◽

Atom Probe ◽

Oxygen Stoichiometry ◽

Specimen Holder ◽

Transmission Electron ◽

Thermally Grown

AbstractWe employed correlative atom probe tomography (APT) and transmission electron microscopy (TEM) to analyze the alumina scale thermally grown on the oxide dispersion-strengthened alloy MA956. Segregation of Ti and Y and associated variation in metal/oxygen stoichiometry at the grain boundaries and triple junctions of alumina were quantified and discussed with respect to the oxidation behavior of the alloy, in particular, to the formation of cation vacancies. Correlative TEM analysis was helpful to avoid building pragmatically well-looking but substantially incorrect APT reconstructions, which can result in erroneous quantification of segregating species, and highlights the need to consider ionic volumes and detection efficiency in the reconstruction routine. We also demonstrate a cost-efficient, robust, and easy-handling setup for correlative analysis based solely on commercially available components, which can be used with all conventional TEM tools without the need to modify the specimen holder assembly.

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The nitrogen effect on the oxidation behaviour of Ti6242S titanium-based alloy: contribution of atom probe tomography

MATEC Web of Conferences ◽

10.1051/matecconf/202032106005 ◽

2020 ◽

Vol 321 ◽

pp. 06005

Author(s):

C. Dupressoire ◽

M. Descoins ◽

A. Vande Put ◽

D. Mangelinck ◽

P. Emile ◽

...

Keyword(s):

Oxide Scale ◽

Atom Probe Tomography ◽

Metallic Matrix ◽

Atom Probe ◽

Oxygen Solubility ◽

Air Oxidation ◽

Low Oxygen ◽

Oxygen Dissolution ◽

Nitrogen Effect ◽

Secondary Oxidant

At high temperatures under oxidizing environments, titanium-based alloys form an oxide scale and dissolve large amount of oxygen in their metallic matrix. Oxygen dissolution is a cause of embrittlement. Nitrogen is a secondary oxidant, which also dissolves in titanium during oxidation in air. Oxidation experiments of Ti-6Al-2Sn-4Zr-2Mo-0.1Si titanium-based alloy at 650 °C for 1000 h in synthetic air (20%O2- 80%N2) and in a mixture of 20%O2-80%Ar, showed that nitrogen reduces both oxide scale growth and oxygen dissolution. Atom probe tomography revealed that nitrogen effect is due to the formation of an interfacial layer of nitride Ti2N but also to the formation of a nitrogen rich a-Ti-based solid solution, which both act as difiusion barriers for oxygen because of their low oxygen solubility.

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