The quality of aviation oils was evaluated online on the basis of their lubricating, antifriction, rheological and antiwear properties in the friction contact. The use of the software and hardware complex for evaluation of operational characteristics of triboelements is offered. Approbation of the proposed methodology was performed on aviation oils SM-9. The increase in antifriction properties of the “Bora B” SM-9 oil was established to be due to the formation of limiting adsorption layers of lubricant on friction-activated contact surfaces, which are characterized by low shear stresses of the lubricant, and their structuring provides high effective viscosity in the contact at a level of 5142 Pa.s. It was revealed that at start-up the lubricant temperature is 20 0С and the mixed lubrication mode prevails, but with increasing the lubricant temperature to 100 0С the elastic-hydrodynamic (contact-hydrodynamic) lubrication mode dominates, then at maximum rotation speed of friction pairs the hydrodynamic lubrication mode dominates, regardless of oil temperature, which indicates the effective separation of the contact surfaces due to the formation of a lubricating layer between them. Analysis of the specific work of friction in the friction contact showed that the instability of this parameter evidences to intensification of destructive processes in the near-surface layers of metal and reduction in its wear resistance. The decrease in wear resistance of the lagging surface in the conditions of rolling with sliding for all types of investigated oils is due to the different directions of the friction force vector in the contact. In the course of operation of friction pairs in nonstationary conditions, the softening of the surface metal layers occurs, which has a positive effect on the tribological processes in the contact. The practical significance of the work consists in developing a methodology of analysis of lubricants, which makes it possible to more accurately evaluate their performance and provide recommendations for the choice of lubricant for specific friction units.

620.178.16(045) and V. N. BorodiiWe analyze the wear resistance of plasma coatings for a constant work of friction. The dependences of the wear resistance of the coatings are obtained for a broad range of loading conditions. It is shown that the minimum sensitivity to loading conditions is exhibited by the molybdenum coatings. It is also established that the wear resistance of the coatings decreases as the amplitude of displacements increases and the cyclic frequency of the tests decreases due to the intensification of fatigue processes on the surfaces. The comparative characteristics of coatings are presented. Introduction.In the contemporary machine building, the operation of components in friction units is, as a rule, connected with wear [1]. At present, plasma coatings are extensively used in the production of building structures, in almost all branches of machine building, power engineering, engine building, aircraft and spacecraft industries, and in many other fields of contemporary engineering. The application of coatings can solve the problems of enhancement of atmospheric resistance, operating stability, adhesion, thermal and erosion resistances and improvement of the protective properties and chemical stability aimed at guaranteeing the required service life of the products [2]. However, the most important problem is the elevation of the wear resistance of the parts and units of machines and mechanisms.The deposition of coatings is one of the most efficient methods of wear protection. At present, there are numerous specially developed technological procedures and a broad class of materials aimed at getting protective coatings with high characteristics of wear resistance. In the production and renovation of the components of aircrafts, it is customary to use wear-resistant coatings obtained by the methods of gas-thermal spraying.The regularities of development of the processes of wear are affected by numerous factors, such as the amplitude of displacements, specific load, frequency of vibration, the type of contact of the mating components, etc.[1]. The variations of these factors affect the processes running in the friction contact and, as a result, the surfaces are damaged. The analysis of the roles of various factors and the availability of the data on the character of development of the processes running in mechanochemical materials makes it possible to substantiate the choice of materials of mating surfaces in the production and renovation of machine parts and the methods of wear protection.The problem of wear resistance of gas-thermal coatings was studied by numerous researchers [3-5, etc.]. Thus, the wear resistance of gas-thermal coatings sprayed by the detonation method was investigated in [3]. These coatings are characterized by low porosity and high adhesive strength. The investigations were carried out in various gaseous atmospheres and liquid media. The ranges of serviceability of the coatings were determined depending on the loading conditions. The coatings applied by the pulsed plasma ...