The article reflects certain applied aspects of a new direction of energy — biosynthetic energy sources, such as bio-oils obtained from technical oils. In particular, there are considered results of the research of the influence of such a characteristic factor of base oils and, first of all, bio-oils as their surface activity on energy efficiency and reliability of operation of friction units lubricated by them under the conditions of the boundary regime of friction. It is proved that the surface activity of oils as an indicator of their functional quality is due to the peculiarities of the structure and properties of their molecules, the energy fields of which evoke certain tribochemical interactions with triboactivated nano-surfaces of friction steels. Separate provisions for evaluating the effect of the tribochemical activity of oils on the process of modifying the steel surfaces of functioning friction units have been formed. The essence of X-ray examination of the influence of lubricating media on the condition of the steel surface by the method of a sliding X-ray beam, analyzing the surface layers with a depth of 0.5–7 mkm. The effect of significant influence of bio-oils obtained from oils on the phase transformations of the structure and properties of the steel surface during tribe tests of samples on friction and wear is revealed. It is established that the effect of obtaining the crystal structure of steel with surface hardening under the deformed layer depends on the tribochemical activity of the proposed three lubricating compositions, which are characterized by the algorithmic growth of such activity. It is proved that the tribochemical activity of bio-oils (in compositions 2 and 3, estimated by the intensity of phase transformations in the surface layers (the effect of Rebinder PO), leads, in turn, to improved friction and wear of lubricated samples compared to the composition 1 low triboactivity. X-structural surfaces analysis of the samples of steel 45 in the initial state and after testing in the media of each of the compositions showed that in the friction processes there is a destruction of the structure of austenite with the release of α-phase (ferrite). It is shown that the intensity of such modification of steel surfaces is progressively amplified in samples lubricated with compositions in accordance with their increasing triboactivity. It was found that with the penetration into the surface layers of steel (from 0.5 to 7 mkm), lubricated with bio-oils of the samples after their tribometer tests, the amount of ferrite increases and the content of austenite decreases. This reduces the deformability of the structure of metal crystals, which leads to the strengthening of its surface under its plasticized layer, and hence the reduction of friction and wear due to the formed intersurface servito-tribopolymer film, resistant to friction. Bibl. 12, Fig. 5, Tab. 3.
Structural and phase transformations in cast irons when implanted into the surface layers of nitrogen ions
