LAUSR

This paper focuses on the influence of diffusion and segregation processes on the strength and tribological characteristics of friction units. The application of the quantum chemical method made it possible to reveal that the appearance of segregated atoms at the grain boundaries is the main reason for hardening or destruction of metal surface layers. The proposed approach was also applied to assess the compatibility of various elements consisting of iron and to relate this compatibility to the tribological characteristics. Comparative tests on friction and wear were aimed at investigating initial 38Х2МЮА-Ш nitrated steel, 38Х2МЮА-Ш nitrated steel with a diamond-like coating, and Nb- and Hf-alloyed 38Х2МЮА-Ш nitrated steel with a diamond-like coating. The tribospectral identification method proposed by the authors was used to study the friction processes in heavily loaded friction units using the example of Mi-26 helicopter spline joints.