Utilize este identificador para referenciar este registo:
https://hdl.handle.net/1822/70446
Título: | An experimental and theoretical study on the crystal structure and elastic properties of Ta1-xOx coatings |
Autor(es): | Almeida Alves, C. F. Marques, L. Calderon, S. V. Ferreira, P. J. Schneider, D. Cavaleiro, A. Carvalho, S. |
Palavras-chave: | Tantalum oxide coatings Magnetron sputtering Ab-initio STEM Elastic modulus |
Data: | 25-Abr-2019 |
Editora: | Elsevier 1 |
Revista: | Surface and Coatings Technology |
Resumo(s): | The production of Ta1-xOx coatings has attracted a lot of attention due to their wide variety of industrial applications. Nonetheless, to properly control the functional properties of these coatings, a good understanding of their structural properties must be achieved. Ta1-xOx phases have structural similarities since they are formed by the distortion of the body centered cubic (bcc) Ta structure and, therefore, a clear and unequivocal identification of the crystalline phases is not trivial. In this regard, this work proposes a theoretical and experimental study to understand the evolution of the structural and the elastic properties of Ta-based coatings. The coatings were deposited by magnetron sputtering as a function of oxygen content and characterized by EPMA (electron probe microanalysis), XRD (X-ray diffraction), STEM (scanning transmission electron microscopy) and SAW (surface acoustic waves). The results demonstrate the formation of a bcc alpha-Ta phase in the non-reactive Ta coating, which transitions to a mixture of crystalline tantalum and tantalum oxide phases for low oxygen concentrations while amorphous phases are observed for high oxygen levels. Ab-initio calculations of different Ta-O phases are in good agreement with the experimental results and reveal that the oxygen addition to the metallic Ta phase, leads to a distortion of the Ta crystal structure, causing a decrease in density and an increase of the elastic constants. |
Tipo: | Artigo |
URI: | https://hdl.handle.net/1822/70446 |
DOI: | 10.1016/j.surfcoat.2019.02.054 |
ISSN: | 0257-8972 |
Versão da editora: | https://www.sciencedirect.com/science/article/pii/S0257897219301999 |
Arbitragem científica: | yes |
Acesso: | Acesso aberto |
Aparece nas coleções: | CDF - FCT - Artigos/Papers (with refereeing) |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
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1-s2.0-S0257897219301999-main (1).pdf | 2,95 MB | Adobe PDF | Ver/Abrir |