First-principles study of an interfacial phase diagram in the V-doped WC-Co system
Artikel i vetenskaplig tidskrift, 2012

We present a method of determining an interfacial phase diagram using density functional theory calculations for interface energetics. Cluster expansions based on these calculations are used in Monte Carlo simulations to obtain configurational free energies. The method is applied to study the segregation of V to the WC(0001)/Co interface and to construct the corresponding interface diagram, a "complexion" phase diagram. By CALPHAD-type analysis for the adjoining bulk phases, a connection with real materials is made. We find that, in equilibrium, the interface contains a thin V-rich film for a wide range of temperatures and chemical potentials of V corresponding to V additions below the (V, W)C-x solubility limit. The results are compared with available experimental data, and implications of the strong segregation of V for the sintering process of V-doped WC-Co are discussed.

density functional theory

cemented carbides

metal-ceramic interfaces

segregation

films

WC/Co interfaces

Författare

Sven Johansson

Chalmers, Teknisk fysik, Material- och ytteori

Göran Wahnström

Chalmers, Teknisk fysik, Material- och ytteori

Physical Review B - Condensed Matter and Materials Physics

1098-0121 (ISSN)

Vol. 86 3 035403-

Styrkeområden

Nanovetenskap och nanoteknik

Materialvetenskap

Ämneskategorier

Fysik

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.1103/PhysRevB.86.035403