The results of theoretical and experimental investigations of frictional pairs, carried out by the IF and AE methods, are generalized and discussed. The use of information in respect to the energy fluxes distribution allows to explain some nontrivial changes of structural states, contacting surfaces strengthening, intensified adhesive processes in thin undersurface layers of contacting materials. It allows to define the effective thickness of defective layer. A workload possibility of layered materials with required quality parameters is examined. The methods of material matching for frictional units are also considered.