Visualising microstructural dynamics of titanium aluminium nitride coatings under variable-temperature oxidation
(2023) In Applied Surface Science 618.- Abstract
Understanding the link between titanium-aluminium nitride's (Ti1-xAlxN) physicochemical properties and structural dynamics during operation is essential to designing and fabricating advanced ceramic coatings. Here, we directly visualise the oxidation of Ti1-xAlxN (for x = 0, 0.18, 0.44, & 0.67) coatings from 100 to 1000 °C using environmental transmission electron microscopy (ETEM) imaging and energy dispersive X-ray spectroscopy (EDX) analysis. The high-frame-rate ETEM movies show that oxidation in TiN proceeds at the grain boundaries and cracks; in contrast, Ti1-xAlxN coatings transform from large as-deposited grains into oxide nanoparticles. Moreover,... (More)
Understanding the link between titanium-aluminium nitride's (Ti1-xAlxN) physicochemical properties and structural dynamics during operation is essential to designing and fabricating advanced ceramic coatings. Here, we directly visualise the oxidation of Ti1-xAlxN (for x = 0, 0.18, 0.44, & 0.67) coatings from 100 to 1000 °C using environmental transmission electron microscopy (ETEM) imaging and energy dispersive X-ray spectroscopy (EDX) analysis. The high-frame-rate ETEM movies show that oxidation in TiN proceeds at the grain boundaries and cracks; in contrast, Ti1-xAlxN coatings transform from large as-deposited grains into oxide nanoparticles. Moreover, high-resolution ETEM imaging show the presence of anatase TiO2 at the early stages of oxidation across all compositions. Above ∼ 850 °C, the oxide nanoparticles grow through crystal merging, diffusion and recrystallisation to form rutile TiO2. The EDX elemental maps coupled with secondary electron imaging reveal a uniform TiO2 sublayer decorated with increasing coverage of Al2O3 particles for x = 0.18 to 0.44. In contrast, coatings with x = 0.67 reveal a complete in-plane phase separation of Al- and Ti-oxides, which can rationalise their decreasing long-term oxidation resistance. Finally, the study provides unique insight into the real-time structural dynamics underpinning the oxidation resistance of Ti1-xAlxN coatings.
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- author
- Makgae, Ofentse A. LU ; Lenrick, Filip LU ; Bushlya, Volodymyr LU ; Andersson, Jon M. ; M'Saoubi, Rachid LU and Ek, Martin LU
- organization
- publishing date
- 2023-05-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Coatings, Environmental TEM, In situ oxidation, Thin films, Titanium aluminium nitride
- in
- Applied Surface Science
- volume
- 618
- article number
- 156625
- publisher
- Elsevier
- external identifiers
-
- scopus:85147551635
- ISSN
- 0169-4332
- DOI
- 10.1016/j.apsusc.2023.156625
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2023 The Author(s)
- id
- 7b96160a-7ebf-41d6-b113-0d830cf9134a
- date added to LUP
- 2023-02-17 16:43:35
- date last changed
- 2024-03-18 20:32:03
@article{7b96160a-7ebf-41d6-b113-0d830cf9134a, abstract = {{<p>Understanding the link between titanium-aluminium nitride's (Ti<sub>1-x</sub>Al<sub>x</sub>N) physicochemical properties and structural dynamics during operation is essential to designing and fabricating advanced ceramic coatings. Here, we directly visualise the oxidation of Ti<sub>1-x</sub>Al<sub>x</sub>N (for x = 0, 0.18, 0.44, & 0.67) coatings from 100 to 1000 °C using environmental transmission electron microscopy (ETEM) imaging and energy dispersive X-ray spectroscopy (EDX) analysis. The high-frame-rate ETEM movies show that oxidation in TiN proceeds at the grain boundaries and cracks; in contrast, Ti<sub>1-x</sub>Al<sub>x</sub>N coatings transform from large as-deposited grains into oxide nanoparticles. Moreover, high-resolution ETEM imaging show the presence of anatase TiO<sub>2</sub> at the early stages of oxidation across all compositions. Above ∼ 850 °C, the oxide nanoparticles grow through crystal merging, diffusion and recrystallisation to form rutile TiO<sub>2</sub>. The EDX elemental maps coupled with secondary electron imaging reveal a uniform TiO<sub>2</sub> sublayer decorated with increasing coverage of Al<sub>2</sub>O<sub>3</sub> particles for x = 0.18 to 0.44. In contrast, coatings with x = 0.67 reveal a complete in-plane phase separation of Al- and Ti-oxides, which can rationalise their decreasing long-term oxidation resistance. Finally, the study provides unique insight into the real-time structural dynamics underpinning the oxidation resistance of Ti<sub>1-x</sub>Al<sub>x</sub>N coatings.</p>}}, author = {{Makgae, Ofentse A. and Lenrick, Filip and Bushlya, Volodymyr and Andersson, Jon M. and M'Saoubi, Rachid and Ek, Martin}}, issn = {{0169-4332}}, keywords = {{Coatings; Environmental TEM; In situ oxidation; Thin films; Titanium aluminium nitride}}, language = {{eng}}, month = {{05}}, publisher = {{Elsevier}}, series = {{Applied Surface Science}}, title = {{Visualising microstructural dynamics of titanium aluminium nitride coatings under variable-temperature oxidation}}, url = {{http://dx.doi.org/10.1016/j.apsusc.2023.156625}}, doi = {{10.1016/j.apsusc.2023.156625}}, volume = {{618}}, year = {{2023}}, }