Artemchuk V. Scientific substantiation of recovering the parts by layered coatings in repair of railway rolling stock.

Processes of recovering and strengthening the parts reliability during a repair of mechanical section of the railway rolling stock have been chosen as an object of investigation. The parts and devices of mechanical section of the railway rolling stock are a theme of investigation. Research methods. Such methods for investigating the structure as metallography, X-ray diffraction phase analysis, X-ray spectrum microanalysis, and chemical analysis are under application. Some methods of testing for adhesion, wear resistance of coatings, and other mechanical properties of coatings are used. The methods of probability and reliability theories for estimating the indices of reliability of parts and technological recovering processes are applied. The thesis is devoted to solving the scientific problem of increasing the service life and reliability of operation of rolling stock during its repair. The problem of determining the relations between the parameters of technological processes for recovery of railway rolling stock parts, the structure and the properties of layered coatings is formulated and solved. It is shown in the thesis that by adjusting the parameters of the coating technological process of depositing, the layers can be obtained with the anticipated properties. A mathematical model to determine the rational parameters of recovering layered coating of the rolling stock parts during a repair, which enables the company to set rational modes and technology of recovering the worn taking into account the cost indices of the process is developed and presented in the thesis. Using the vector optimization instruments, an algorithm for assessment of the quality of recovering the rolling stock parts in several indices is suggested. The recommendations on the choice of modes, technologies and techniques of recovering the worn rolling stock parts by the layered coatings ensuring the high quality and reliability of operation of parts selected are developed. The procedure for estimating the reliability of parts recovered by layered coatings, which allows determining the probability of failure-proof operation of these parts taking into account the wear of material of the layers as a random value, is suggested. The thesis results are introduced and at the stage of preparation to further implementation. A sphere of usage is the railway rolling stock.