Title :
Direct TEM observation of the welding of asperities between two single crystal gold films
Author_Institution :
Bell Commun. Res., Red Bank, NJ, USA
Abstract :
The information of grain boundaries between two gold films in contact was directly observed on a hot stage in a transmission electron microscope at a temperature that was less than 0.4 of the gold melting point. This is believed to be the first direct evidence of metal-to-metal welding by the formation of grain boundaries at touching asperities. These welds can contribute to the frictional force of a sliding contact because grain boundaries of pure metals have the same mechanical strength as the bulk of the material. In addition, shear deformation of these joined asperities can contribute to the adhesive wear in sliding. This would be relevant to the gold alloys used in electrical sliding contacts. The experimental results are reported in detail.<>
Keywords :
electrical contacts; friction; gold; grain boundaries; materials testing; metallic thin films; transmission electron microscope examination of materials; wear; Au-Au contacts; adhesion; adhesive wear; direct TEM observation; electrical sliding contacts; experimental results; formation of grain boundaries; frictional force; hot stage; mechanical strength; metal-to-metal welding; pure metals; shear deformation; single-crystal Au films; sliding contact; transmission electron microscope; two single crystal gold films; welding of asperities; Adhesives; Contacts; Friction; Gold alloys; Goniometers; Grain boundaries; Substrates; Temperature; Transmission electron microscopy; Welding;
Conference_Titel :
Electrical Contacts, 1988., Proceedings of the Thirty Fourth Meeting of the IEEE Holm Conference on
Conference_Location :
San Francisco, CA, USA
DOI :
10.1109/HOLM.1988.16116
