A Review on Treating Tribological Problems with Fractals

Abstract

Abstract Fractals and chaos theory provide means of modeling dynamic changes in micro and nano topography on friction surfaces caused by various tribological mechanisms and processes. Friction and wear phenomena in tribological systems can be interpreted on a macroscopic scale. With the development of miniaturized scale and nanoscale systems, it has been launched the hypothesis that macro-level systems cannot reflect the microscale and nanoscale phenomena. A conclusive case is given by the calculation of frictional torque in microscale orientation, in this situation being found that models created by bearing producers cannot validate experimental results. By applying the “box-counting” method, it is possible to estimate the fractal dimension both directly and indirectly by comparing the area-perimeter-scale relations. Based on scaling equations, a system was created for this operation. The conclusion is that all existing theories in tribology should be adapted to take into account fractal size and fractal roughness.