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Information × Registration Number 0211U002494, 0109U001886 , R & D reports Title Dynamic and structural integrity of thin coating of contact surface for responsible engineer construction at vibrating loading popup.stage_title Head Kostogrys C. H., Registration Date 10-02-2011 Organization Khmelnytskiy National University popup.description2 Object of research - frictional contact in the joints of machine parts and structures, which modify the surface of protective coatings. Subject of research - ensure efficiency friction joints and increase their fretting-resistance based on experimental research and development of the theory of dynamic frictional contact. Methods of research - stress components in contact found by numerical solution of singular integral equations of the first kind in the half space with a given distribution of normal and tangential efforts. Experimental studies performed by schemes ball-plane, plane-plane in a wide range of normal pressures, frequencies and amplitudes of vibration disturbance. Research microgeometry and quantification characteristics of microdamages carried out by laser scanning of surfaces in three dimensions. Comprehensive coatings of construction materials were created by doping electric-spark WC8 hard alloy and subsequent laser irradiation. Theoretical and practical results: The concept of four-evolutionary model of fretting process as an open dynamic system was developed. The mathematical model consists of a system of differential equations; first consider the "mobility" of thin surface layers autonomously with respect to all the details. Contact problem is solved for the contact surfaces with a thin coating with partial slippage and based on the criterion of Huber- Mises. Novelty: 1) found analytical solutions to describe the vibration characteristics of the friction parameter, taking into account the plasticity at the Stribek effect the transition to slip, and viscosity in the transition to the kinematics friction; 2) developed and described mathematically complex stress for the mixed fretting contact, which allows to determine the mechanism of degradation of contact spots in the presence of zones of adhesion, slippage and experimentally verify analytical solutions; 3) the influence of thin surface layer with properties different from the basic material, the evolution of a dynamic picture of fretting process that first explains the role of thickness and density of the modified layer or coating to reduce the relative mobility of small amplitude at fretting contact pair; 4) a method of surface treatment (electric-spark following discrete doping and laser melting) propose a way of reinforcing contact surfaces to improve the structural integrity of the contact pair. Applications: machine-building enterprises, electronic industry, factory laboratories, and colleges. Product Description popup.authors Костогриз Сергiй Григорович Морозов С.В. Плахотнік Г.І. Шалапко Ю. I. popup.nrat_date 2020-04-02 Close