Universidad Complutense de Madrid
E-Prints Complutense

Ab initio study of decohesion properties in oxide/metal systems

Impacto

Downloads

Downloads per month over past year

Beltrán Finez, Juan Ignacio and Muñoz, M.C. (2008) Ab initio study of decohesion properties in oxide/metal systems. Physical review B, 78 (24). ISSN 1098-0121

[img]
Preview
PDF
262kB

Official URL: http://dx.doi.org/10.1103/PhysRevB.78.245417


URLURL Type
http://journals.aps.org/Publisher


Abstract

Several studies of the decohesion properties of various oxide/metal systems have been performed recently by ab initio calculations. However, the use of different computational methods, which involve diverse approximations, energy functionals, or calculation conditions, makes the identification of general trends difficult. In the present work, a broad range of interfaces between an ionic oxide (Al_(2)O_(3), ZrO_(2), HfO_(2), and MgO) and a metal [either transition metal (TM) or Na], has been investigated systematically in order to find correlations among the work of separation (Wsep) and the intrinsic properties of the interface, such as the crystal structure, the strain conditions, or the electronic properties of both constituents. Our main result is that the calculated Wsep adjusts very accurately to a parabolic dependence on the summed surface energies of the metal and the oxide, regardless of the oxide and metal components, crystal lattices, interface orientations, and atomic terminations. Furthermore, Wsep is mostly determined by the surface energies although for interfaces involving nonpolar oxide surfaces the contribution of the interfacial energy is not negligible. The strongest adhesion is found for interfaces formed by polar surfaces and bcc TM, e.g., the Wsep of ZrO_(2)(001)_(O)/TM interfaces changes almost by a factor of 2 depending on whether the TM has bcc or fcc structure. In addition, a correlation between the strain conditions of the equilibrium interface structure and the adhesion properties has been obtained. Finally, in order to predict metal/oxide systems whose mechanical properties are reinforced by the plastic deformation of the metal, we examine the expected behavior of the system beyond the elastic regime in the light of the calculated adherence at the interface. The comparison with the scarcely available experimental data provides good agreement for both the Wsep and the qualitative prediction of mechanical reinforcement.


Item Type:Article
Additional Information:

© 2008 The American Physical Society. We are very grateful to J.F. Bartolomé, S. Gallego, C. Pecharromán, and J.S. Moya for many fruitful discussions. This work was supported by the Spanish Ministry of Education and Science under Project No. MAT2006-05122.

Uncontrolled Keywords:Metal-ceramic interfaces; Structural-properties; Single-crystals, 1st principles; Adhesion; Zirconia; Surface; Adsorption; Fracture; Films.
Subjects:Sciences > Physics > Electricity
Sciences > Physics > Electronics
ID Code:31403
Deposited On:27 Jul 2015 09:33
Last Modified:10 Dec 2018 14:58

Origin of downloads

Repository Staff Only: item control page