Ternopil Ivan Pul'uj National Technical University

About: Ternopil Ivan Pul'uj National Technical University is a(n) based out in . It is known for research contribution in the topic(s): Deformation (engineering) & Fracture toughness. The organization has 134 authors who have published 187 publication(s) receiving 1019 citation(s).

Assessment of lifetime of railway axle

Abstract: Main laws of influence of stress ratio on fatigue crack growth rate in the material of railway axles were revealed and statistical distributions of characteristics of cyclic crack’s resistance for steel were determined. The technique of modelling of fatigue crack growth in the material of railway axle under regular and random loading was developed, taking into account statistical characteristics of mechanical properties. It gives the ability to obtain statistical distribution of final crack depth for the given number of loading cycles and the distribution of lifetime for the given before final crack depth.

Scale levels of damage to the raceway of a spherical roller bearing

Abstract: The study determines the parameters of defects generated in a roller bearing used in the link of a mould oscillating mechanism that makes part of a continuous billet-casting machine. The evolution of such defects is described from the perspective of scale levels of deformation and fracture. The studied wear behaviour in the bearing corresponds to false brinelling; the raceways suffer the formation of grooves having the bottom with folded morphology. The mechanisms of deformation and wear of the bearing were analysed using multi-level approach, i.e. at macro-level, from the perspective of the mechanics of a deformable rigid body, at meso-level II, implementing tribological approaches, and at meso-level I, using the methods of indentation, three-dimensional profilometry and fractography.

Fatigue and brittle fracture of carbon steel of gas and oil pipelines

Abstract: The areas of low frequency and corrosion fatigue for basic metal and welding joints of oil and gas pipelines have been determined on the basis of corrosion-fatigue test results. The most dangerous diapasons of the operation loadings were also determined. The present work also proposes the methodical approaches to the survivability prediction.

Enhancing plasticity of high-strength titanium alloys VT 22 under impact-oscillatory loading

Abstract: The purpose of this paper is to provide new experimental data for high-strength VT 22 titanium α + β-type alloy under impact-oscillatory loading and dynamic non-equilibrium process. Based on the performed experimental studies, it was found that overall plastic deformation of this alloy can be increased by a factor 2.75 compared with its initial state without significant loss of strength. To achieve this goal, a new methodology to study the impact behaviour of materials under non-equilibrium process has been used. Physical research revealed that significant microstructural refinement of the alloy is observed after such type of loading, as the result of which the fine grains are formed with subgrain refinement which takes place within the basis of alloy.

Degradation of the main gas pipeline material and mechanisms of its fracture

Abstract: The effect of the in-service scattered damage in the pipe wall metal is evaluated, and the effect of hydrogen absorbed by metal on the variation of the structure and mechanical properties of the main gas pipeline after a long-term operation is found. The main regularities in the graded nature of the static deformation process and the effect of hydrogenation on the scattered damage and fracture accumulation are found.