Nanomechanical characterization of nanostructured La2(Zr0.75Ce0.25)2O7 thermal barrier coatings by nanoindentation

• Published in: Applied surface science Vol. 505; p. 144585
• Main Authors: Zhou, F.F., Xu, L.P., Deng, C.M., Song, J.B., Deng, C.G., Wang, Y., Liu, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2020
• Subjects: Atmospheric plasma spraying; Indentation work; Microhardness dissipation parameter (MDP); Nanomechanical properties; Nanostructured La2(Zr0.75Ce0.25)2O7 coatings; Atmospheric plasma spraying; Nanostructured La2(Zr0.75Ce0.25)2O7 coatings; Microhardness dissipation parameter (MDP); Nanomechanical properties; Indentation work
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.144585

•The elastic modulus and nano-hardness of nanostructured La2(Zr0.75Ce0.25)2O7 coatings are sensitive to non-molten zones.•The elastic work is insensitive to microstructure while the plastic work is sensitive to microstructure of coatings.•The microhardness dissipation parameter is 0.672 ± 0.042.
Nanostructured rare-earth zirconates materials have a great potential in next generation ultra high temperature thermal barrier coatings. In this work, the nanostructured La2(Zr0.75Ce0.25)2O7 coatings were fabricated by atmospheric plasma spraying using as-prepared nanostructured La2(Zr0.75Ce0.25)2O7 spherical feedstocks and nanomechanical properties of coatings were characterized by nanoindentation in detail. Results indicate that the grain growth of nanostructured coating is not obvious compared with feedstocks. The elastic modulus and nano-hardness of coatings, which are sensitive to non-molten zones, are 116.483 ± 19.236 GPa and 5.715 ± 1.656 GPa, respectively. The elastic indentation work is 11.465 ± 0.750 nJ and the plastic indentation work is 23.981 ± 5.035 nJ. The parameter of energy dissipation during plastic deformation (microhardness dissipation parameter, MDP) is 0.672 ± 0.042, indicating that outstanding properties under wear conditions for nanostructured La2(Zr0.75Ce0.25)2O7 coatings.