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Information × Registration Number 0217U000202, 0114U004001 , R & D reports Title Evaluation of the tribojoint durability considering the fracture of materials, residual stresses and heat popup.stage_title Head Panasyuk Volodymyr; Datsyshyn Oleksandra, Registration Date 31-01-2017 Organization Karpenko Physico-Mechanical Institute of the National Academy of Sciences of Ukraine popup.description2 Object of research: contact durability of tribojoint elements. The work purpose: The methods development of estimation of durability of tribojoint contacting pairs by criteria of formation of typical contact fatigue damages in a contact zone of of rolling pairs and fretting pair taking into account residual stresses, heat formations and materials crack resistans characteristics. Research methods: method of singular integral equations for bodies with cracks, mechanical quadratures method, mass forces method of, approaches of fatigue fracture mechanics. The basic results: Within the frame of two-stage estimation model of contact residual durability of solids subjected to cyclic loading, the methodology of computer research of cracks propagation and contact fatigue damages formation has been developed, and also an estimation of tribojoint contact durability has been implemented taking into account operational parametres of joints, materials cyclic crack resistanse characteristics, and also nearsurface circular residual stresses. Algorithms of step-by-step calculation of cracks growth paths and the decision of problems on cracks faces contact in a zone of compression taking into account mutual moving of contacting bodies and possible change of the mechanism of fracture (transversal shear - normal opening) are developed on the basis of the integral singular equations method. Great volume of data about dependence of parametre of a stress intensity factor range in a contact cycle КII, which control crack growth by the transversal shear mechanism in a contact zone, on a angle of edge crack orientation, operational parametres of "wheel-rail" system and, in particular, residual stresses is received. Presence of a characteristic angle of shear edge cracks propagation is established. Conditions of its definition are written. It is shown, that cracks with this angle are both independent contact fatigue damages, and a basis of formation of such typical contact fatigue damages, as "cracking", "squat", pitting etc. Similar conditions are offered for angle definition that forms "fretting tongue" in fretting pair elements. Subsurface cracks growth paths are constructed and residual contact durability of some rail and wheel steels is estimated for various configurations of operational parametres in system "wheel-rail" and taking into account cyclic crack resistance characteristics of steels on transversal shear and normal opening. Curves of contact fatigue (dependence of rolling cycles quantity (Nf) on maximum value of contact pressure (p0)) by criterion of formation shalling on rolling surfaces are constructed. Application areas: mechanical engineering, a railway transportation, air industry etc. Product Description popup.authors Глазов Артем Юрійович Кравчук Оксана Андріївна Левус Андрій Богданович Марченко Григорій Петрович Пришляк Роман Євгенович Рудавська Ірина Анатоліївна popup.nrat_date 2020-04-02 Close