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DOE OSTI · 22490422

Adhesion at WC/diamond interfaces - A theoretical study

Padmanabhan, Haricharan·Rao, M. S. Ramachandra·Nanda, B. R. K.,
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Abstract

We investigate the adhesion at the interface of face-centered tungsten-carbide (001) and diamond (001) from density-functional calculations. Four high-symmetry model interfaces, representing different lattice orientations for either side of the interface, are constructed to incorporate different degrees of strain arising due to lattice mismatch. The adhesion, estimated from the ideal work of separation, is found to be in the range of 4 - 7 J m{sup −2} and is comparable to that of metal-carbide interfaces. Maximum adhesion occurs when WC and diamond slabs have the same orientation, even though such a growth induces large epitaxial strain at the interface. From electronic structure calculations, we attribute the adhesion to covalent interaction between carbon p-orbitals as well as partial ionic interaction between the tungsten d- and carbon p-orbitals across the interface.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYADHESIONCOMPARATIVE EVALUATIONSCOVALENCECRYSTAL DEFECTSDENSITY FUNCTIONAL METHODDIAMONDSELECTRONIC STRUCTUREEPITAXYINTERFACESORIENTATIONSTRAINSTUNGSTENTUNGSTEN CARBIDES

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Padmanabhan, Haricharan, Rao, M. S. Ramachandra, Nanda, B. R. K.,. 2015-06-24. Adhesion at WC/diamond interfaces - A theoretical study. https://doi.org/10.1063/1.4917963

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