Adhesion studies by instrumental indentation testing

The miniaturization of devices and the advances in nanotechnol.-enabled products has led to the requirement of an increased understanding of the various interactions present in nanoscale contacts - including adhesion and surface tension. It is well known that adhesion plays an important role in the tribol. behavior and contact mechanics of many modern nano-devices and will affect future products currently under development. Adhesion of materials is ruled by interactions that extend down to the at. scale of the contributing materials. The forces involved include non-covalent interactions such as Van-der-Waals forces, hydrogen bonds and Coulomb forces as well as covalent chem. bonds. Although Van-der-Waals forces are only short range, they often rule the adhesion between two materials and are therefore responsible for contact interaction between two films. While the adhesion between two materials is one important factor, the elasticity of both is also very important. This elasticity has a major influence on the size of a contact area that is developed underneath a point contact when a certain force is active. Modern instruments for nanoindentation are sensitive enough to detect the small surface forces and to study adhesion effects. [on SciFinder (R)]