Density functional theory calculations were performed to study the effects of H, He, Li and Be on the cohesion of W S3{112} and S27{552} grain boundaries (GBs). In S3, Li causes the strongest embrittlement, while in S27 it is He. In both GBs, H slightly reduces the cohesion. Compared to He and Li, H exhibits much stronger attractive binding with W that may inhibit subsequent segregation of Li and He to the GBs. In S3, Be decreases the cohesion. However, in S27, Be strengthens the cohesion in several interstitial positions by increasing the bonding across the interface or by inducing GB restructuring.
Revised: April 21, 2014 |
Published: March 13, 2014
Citation
Setyawan W., and R.J. Kurtz. 2014.Ab initio study of H, He, Li and Be impurity effect in tungsten S3{112} and S27{552} grain boundaries.Journal of Physics: Condensed Matter 26, no. 13:Article No. 135004.PNNL-SA-92638.doi:10.1088/0953-8984/26/13/135004