tailieunhanh - Handbook of Micro and Nano Tribology Episode 1 Part 6

Tham khảo tài liệu 'handbook of micro and nano tribology episode 1 part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Colchero J. et al. Friction on an Atomic Scale Handbook of Micro Nanotribology. Ed. Bharat Bhushan Boca Raton CRC Press LLC 1999 1999 by CRC Press LLC 6 Friction on an Atomic Scale Jaime Colchero Ernst Meyer and Othmar Marti Introduction Instrumentation The Force-Sensing System The Tip Experiments Atomic-Scale Imaging of the Friction Force Thin Films and Boundary Lubrication Nanocontacts Quartz Microbalance Experiments in Tribology Modeling of an SFFM Resolution in SFFM Deformation of Tip and Sample Modeling of SFM and SFFM Energy Dissipation on an Atomic Scale Summary Acknowledgments References Introduction The science of friction . tribology is possibly together with astronomy one of the oldest sciences. Human interest in astronomy has many reasons the awe experienced when observing the dark and endless sky the fear associated with phenomena such as eclipses meteorites or comets and perhaps also practical issues such as the prediction of seasons tides or possible floods. By contrast the interest in tribology is purlye practical to move mechanical pieces past each other as easily as possible. This goal has not changed essentially since tribology was born. Ultimately the person who a few thousand years ago had the brilliant idea to pour water between two mechanical pieces was working on the same problem as the expert tribologist today the only difference being their level of knowledge. A better understanding of friction and wear could save an enormous amount of energy and money which would be positive for economy and ecology. On the other hand friction is not only negative since it is fundamental for basic technological applications brakes as well as screws are based on friction. The first approach to tribology is due to Leonardo da Vinci at the beginning of the 15th century. In a certain sense he introduced the idea of a friction coefficient. For smooth surfaces he found that friction corresponds to one fourth its weight in other words .