Atomic-layer expulsion in nanoindentations on an ionic single crystal
Abstract
Utilizing atomic-force microscopy, we have performed and characterized nanoindentations on a MgO(100) surface with depths varying between one monatomic layer and tens of nm. Our results show that plastic deformation is indicated by discrete events in the indentation curve which are associated with the number of atomic layers being expelled by the tip penetrating the surface. An estimation of the energy required to expel MgO ions from a monatomic deep cavity correlates well with our data. The critical shear strength was evaluated and lies in the same order of magnitude as the theoretical value.
- Publication:
-
Applied Physics Letters
- Pub Date:
- August 2000
- DOI:
- 10.1063/1.1306909
- Bibcode:
- 2000ApPhL..77..839T
- Keywords:
-
- 68.35.Gy;
- 62.20.Qp;
- 61.16.Ch;
- 68.35.Bs;
- 62.20.Fe;
- Mechanical properties;
- surface strains;
- Tribology and hardness;
- Structure of clean surfaces;
- Deformation and plasticity