Processes taking place in the contact of two bodies and having an influence on strength and service life of machinery or of the whole structure have been in the interest of physicists and engineers for a very long time. The first scientific base had been created by H. Hertz (see Hertz. H.: tJber die Beruhrung. fester elastischer Korper. J. reine und angewandte Mathematik. 1882. 92. pp. 156-171 ) more than one hundred years ago. Since that time (proportionally to the need of industry) countless numbers of other studies have originated, But practice always has been an inspiration for the...