Tribology laws

Friction is the tangential resistance offered to the sliding of one solid over another, due to dry friction. Friction is an apparently simple phenomenon with very complex mechanisms that take place on a variety of length scales, from atomic to nano and up. The study of friction is part of the engineering-scientific discipline of tribology,3 which is the scientific study of friction, wear, and lubrication (6). It was Leonardo da Vinci (1452-1519) who discovered the first two laws of friction, namely, that the area of contact has no effect on friction and that friction is proportional to the load. These two laws were rediscovered later by Guillaume Amontons (1663-1705), and later Charles-Augustin Coulomb (1736-1806), added the third law ... 

The laws of Unear acoustics are violated at high ampUtudes of oscillation. Studying nonlinear interactions between the crystal and the sample should be useful in the context of tribology and adhesion. 

Y. Sun and T. Bell Effect of layer thickness on the rolling-sliding wear behavior of law- temperature plasma-carburized austenitic stainless steel. Tribology Letters (2002) 13,1, 29-34 Y. Sxm, Kinetics of low temperature plasma carburizing of austenitic stainless steels, J. Mater. Proc. Tech. 168 (2005) 189-194. 

In the search for a calibration of this numerical calculation of film thickness consider the model used almost exclusively by tribology, the Prandtl-Eyring law, which is written for the generalized viscosity, tj. 

The film thickness for the ordinary shear-thinning response of lubricants which can be measured is now calculated. There are many generalized Newtonian fluid models that will describe the shear response displayed in Figures 1 and 2 [16]. The Ree-Eyring model utilizes a series in inverse hyperbolic sine to approximate power-law behavior at high shear rate. In others [16] the power-law exponent, , appears explicitly. Today the most widely used model outside of tribology is the Carreau equation [17] that was advanced to describe the results of molecular network theory. 

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