A computational study of special grain boundaries in WC–Co cemented carbides
Journal article, 2014

In this work, we model Sigma = 2 and Sigma = 1 {10 (1) over bar0}parallel to{10 (1) over bar0} WC/WC boundaries in WC-Co using density functional theory (DFT). In particular, the misfit structure of the Sigma = 2 twist boundary is modeled explicitly with a previously developed Peierls-Nabarro model for misfit dislocations. The grain boundary energy of the twist boundary is found to be 0.7 J/m(2), which is small in comparison with energies of general WC/WC boundaries. The misfit structure can be described as a square network of screw dislocations with Burgers vectors 1/6 < 1 (2) over bar 13 >. Our calculations show that Co will not segregate to the Sigma = 2 twist boundary, which contrasts with predictions for other WC/WC boundaries that typically give half a monolayer of segregated Co.

Cemented carbides

Grain boundary energy

Density functional theory

Grain boundary segregation

Author

Sven Johansson

Chalmers, Applied Physics, Materials and Surface Theory

Martin Petisme

Chalmers, Applied Physics, Materials and Surface Theory

Göran Wahnström

Chalmers, Applied Physics, Materials and Surface Theory

Computational Materials Science

0927-0256 (ISSN)

Vol. 98 345-353

Infrastructure

C3SE (Chalmers Centre for Computational Science and Engineering)

Areas of Advance

Materials Science

Subject Categories

Condensed Matter Physics

DOI

10.1016/j.commatsci.2014.11.024

More information

Created

10/7/2017