Вісник № 46
Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/27259
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Документ Consideration the influence of residual stresses and creep strains on rolling the steel sheets(NTU "KhPI", 2016) Breslavsky, D. V.; Mietielov, V. O.The method for considering the residual stresses which occur by plastic deformation during the rolling process in creep stress-strain state of steel plates in tension is discussed. The problem’s solution is divided on two stages. First one presents the modeling of the problem of plasticity with consideration of finite strains. The rolling process of steel sheets with two rolling mills is regarded. The scheme of technological process and its numerical simulation are described. Obtained stress-strain field in a plate after rolling was considered as a residual for creep initial-boundary value problem, which presents the second stage of analysis. The mathematical problem statement including state equations are built by use of the determined anisotropic creep properties of considering steel 3 at room temperature is presented. The transition procedure from three dimensional to two dimensional stress strain state in considered plate is discussed. Creep problem solution was done by use of developed two-dimensional Finite Element Method codes which include time step integration schemes. The numerical results like stress and strain fields, dependencies between the traction values and maximum plate’s displacements, deformed shape of the plate edge as well as the recommendations for safety conditions of technological process are presented.Документ Web tools for long term strength data processing(NTU "KhPI", 2016) Breslavsky, D. V.; Breslavska, O. O.; Kozlyuk, A. V.The paper concerns the questions of development the specialized web-based software for processing of the long term strength data. The goal is to develop the web tools which could fill up the gap between high theoretical background in Continuum Damage Mechanics and insufficient knowledge about the experimental data by way of storage them and processing the values of constants. The approach for storing of the experimental physical and mechanical properties for different temperatures is described. The structure of database as well as the interface section for selection of different data sets, which include the fracture stress values with appropriate values of time, are presented. Selected fields of database are used for deriving the constants for damage kinetic equations. Two algorithms of deriving are discussed, the first was designed for constant temperature conditions as well as the second assigns for definite interval of temperatures. The numbers of experimental data sets for each algorithm are determined. The example of the deriving process for nickel based alloy is presented and plots of time dependencies for damage parameter are built. The discussed software is designed for engineers and research associates who are working in area of modeling of high temperature properties in materials and structural elements.