Hydrogen effect on shearing and cleavage of Al: A first-principles study
Abstract
We report on first-principles calculations of the effect of a (111) hydrogen layer embedded in Al on generalized stacking fault energies and cleavage energy for different choices of the slip and cleavage planes. It is shown that the H layer softens Al against shear by reducing the stable and unstable stacking fault energies relative to pure Al. This finding points to a possible enhancement of plasticity of Al by H. The H layer also reduces the cleavage energy on the (111) plane. The reductions in the cleavage energy and unstable stacking fault energy compensate each other and produce only a moderate change in the Rice criterion of ductile versus brittle fracture.
- Publication:
-
Physical Review B
- Pub Date:
- September 2011
- DOI:
- 10.1103/PhysRevB.84.104103
- Bibcode:
- 2011PhRvB..84j4103A
- Keywords:
-
- 61.72.Nn;
- 61.72.S-;
- 62.20.F-;
- 62.20.mm;
- Stacking faults and other planar or extended defects;
- Impurities in crystals;
- Deformation and plasticity;
- Fracture