Fundamentals of Tribology and Bridging the Gap Between the Macro- and Micro/Nanoscales

The word tribology was fIrst reported in a landmark report by P. Jost in 1966 (Lubrication (Tribology)-A Report on the Present Position and Industry's Needs, Department of Education and Science, HMSO, London). Tribology is the science and technology of two interacting surfaces in relative motion and of related subjects and practices. The popular equivalent is friction, wear and lubrication. The economic impact of the better understanding of tribology of two interacting surfaces in relative motion is known to be immense. Losses resulting from ignorance of tribology amount in the United States alone to about 6 percent of its GNP or about $200 billion dollars per year (1966), and approximately one-third of the world's energy resources in present' use, appear as friction in one form or another. A fundamental understanding of the tribology of the head-medium interface in magnetic recording is crucial to the future growth of the $100 billion per year information storage industry. In the emerging microelectromechanical systems (MEMS) industry, tribology is also recognized as a limiting technology. The advent of new scanning probe microscopy (SPM) techniques (starting with the invention of the scanning tunneling microscope in 1981) to measure surface topography, adhesion, friction, wear, lubricant-fIlm thickness, mechanical properties all on a micro to nanometer scale, and to image lubricant molecules and the availability of supercomputers to conduct atomic-scale simulations has led to the development of a new fIeld referred to as Microtribology, Nanotribology, or Molecular Tribology (see B. Bhushan, J. N. Israelachvili and U.