Vladimir P. Radchenko

Samara State Technical University · Dept. of Applied Mathematics and Computer Science

Разработан метод решения задачи расчета напряженно-деформированного состояния в поверхностно упрочненном образце со сквозным поперечным надрезом V-образного профиля при различных значениях угла раскрытия в упругой и упругопластической постановках. Метод базируется на конечно-элементном моделировании и известном начальном напряженно-деформированном...

Предложен и реализован метод прогнозирования ползучести и длительной прочности в условиях вязкого механизма разрушения. Вводится предположение, что у материала при нагружении отсутствуют мгновенно-пластическая деформация и первая стадия ползучести, выполняется гипотеза несжимаемости. В разработанном методе показано, что если для заранее испытанного...

25 марта 2023 г. исполнилось 70 лет известному российскому ученому, почетному работнику высшего и профессионального образования РФ, педагогу, администратору, организатору науки и высшего образования в России доктору физико-математических наук, профессору Леониду Александровичу Сараеву. В статье приведены ключевые библиографические данные Л. А. Сара...

We propose a numerical method for predicting the individual deformation characteristics of structural elements by a leader product. The basis of this method is generalized one-parameter models. These models relate the integral characteristics of the stress state to the integral characteristics of the deformation state in the generalized load genera...

10 февраля 2022 г. исполнилось 60 лет известному ученому в области механики деформируемого твердого тела и прикладной математики, педагогу, организатору науки и высшего образования в России Юрию Николаевичу Радаеву. В статье приведены основные библиографические данные Ю. Н. Радаева, в краткой форме представлены основные научные направления и резуль...

Разработана методика расчета релаксации остаточных напряжений в консольно закрепленном вращающемся цилиндре после процедуры поверхностно-пластического деформирования в условиях ползучести, учитывающая влияние ступенчатого изменения параметров температурно-силового нагружения (разгрузки). Задача моделирует напряженно-деформированное состояние поверх...

The problem of calculating the stress-strain state in the region of through stress concentrators in the form of a transverse notch of semicircular, through and V-shaped shape in a prismatic sample after advanced surface plastic deformation in elastic and elastoplastic formulations based on the finite element method is solved. The initial formulatio...

The results of experimental research on residual stresses and plastic deformations by the hardening of the outer and inner surfaces of thin-walled Kh18N10T steel tubes by means of microbeads are described. A phenomenological model for calculating residual stresses and deformation by two-way tube hardening is proposed. A method for parameterization...

We suggest the phenomenological method of reconstructing the fields of residual stresses and plastic deformations in thin-walled cylindrical tubes made of Х18N10Т steel in the delivery state and after a simultaneous bilateral surface plastic hardening by the vibration-shot blasting of the surface with beads on a special vibrating stand. A cylindric...

Исследуется влияние размеров области поверхностного пластического упрочнения на напряженно-деформированное состояние балки с надрезом полукруглого профиля. Задача сведена к краевой задаче фиктивной термоупругости, при этом начальные (пластические) деформации моделируются температурными анизотропными деформациями в неоднородном температурном поле. Р...

Разработана математическая модель релаксации остаточных напряжений в поверхностно упрочненных цилиндрических элементах статически неопределимых стержневых систем при температурно-силовом нагружении в условиях ползучести. В процессе моделирования решаются следующие задачи: реконструкция напряженно-деформированного состояния в цилиндрическом стержне...

Предложен метод моделирования напряженно-деформированного состояния в поверхностно упрочненных элементах статически не определимых стержневых систем в условиях ползучести на примере трехэлементной несимметричной стержневой системы. Решение задачи состоит из двух этапов: реконструкции напряженно-деформированного состояния после процедуры поверхностн...

Oleg A. Repin, age 71, our colleague, editorial board member of the Journal, Professor, Doctor habilitated of Physical and Mathematical Sciences, passed away on August 4th, 2018, after a long battle with serious disease. Oleg A. Repin was a leading scientist from the field of the theory of partial differential equations. He performed the ambitious...

18 января 2018 г. исполнилось 70 лет доктору физико-математических наук, профессору, заслуженному деятелю науки Российской Федерации Александру Павловичу Солдатову. В настоящей заметке приводятся сведения из научной биографии этого крупного ученого, который хорошо известен в России и за рубежом. Представлены сведения о его вкладе в развитие математ...

26 января 2018 г. исполнилось 75 лет доктору физико-математических наук, профессору Евгению Владимировичу Радкевичу. В настоящей заметке приводятся сведения из научной биографии этого крупного ученого, который хорошо известен в России и за рубежом. Обсуждаются его работы, которые внесли существенный вклад во многие области науки и техники.

We suggest a new stochastic model to calculate the residual stresses in the surface- hardened hollow cylinder under the creep conditions with axial tension. A set of experimental studies was carried outto determine the creep strain distribution along the hardened specimen made of D16T alloy at a temperature of 125 C degrees under four modes of tens...

24 мая 2017 г. исполнилось 60 лет доктору физико-математических наук, профессору, иностранному члену Национальной академии наук Республики Армения Александру Владимировичу Манжирову. В настоящей библиографической заметке приводятся биографические сведения об этом крупном ученом, который хорошо известен в России и за рубежом. Представлены сведения о...

We study effect of anisotropy of surface plastic hardening on formation of residual stresses in solid cylindrical samples and samples with semicircular notch. Experimentally determined one and/or two components of residual stresses in a hardened layer are used as an initial information. We describe calculation method for the rest of diagonal compon...

Dyuis D. Ivlev (1930–2013) is an outstanding scientist in the fields of Continuum Mechanics (theory of Perfect Plasticity and Fracture) and Applied Mathematics. He has much contributed to the mathematical theory of plasticity, especially to study of hyperbolic three-dimensional problems of the perfect plasticity. Dyuis D. Ivlev was born in Chuvashi...

We study experimentally the effect of the axial tension load on the residual stresses relaxation in the surface-hardened hollow cylindrical specimens of D16T aluminium alloy at a temperature of 125 ∘C. The surface is hardened by the air shot-peening. We describe the testing machine and the routine of experiment. The experimental curves of hardened...

This paper describes the effect of thermal exposure (high-temperature exposure) (T = 675◦C) on the residual creep stress relaxation in a surface hardened solid cylindrical sample made of ZhS6UVI alloy. The analysis is carried out with the use of experimental data for residual stresses after micro-shot peening and exposures to temperatures equal to...

The authors carried out a complex (computational and experimental) research of residual stresses in prismatic amples made of EP742 alloy after ultrasonic hardening and he temperature of 650 °C for 100 hours unloaded. The laws of residual stresses distribution over the thickness of the surface-hardened layer were discovered. The experiments proved t...

The standard one-dimensional generalized model of a viscoelastic body and some of its special cases—Voigt, Maxwell, Kelvin and Zener models are considered. Based on the V. Volterra hypothesis of hereditary elastically deformable solid body and the method of structural modeling the fractional analogues of classical rheological models listed above ar...

We developed the method for solving the problem of residual stresses relaxation in surface-hardened layer of half-space under creep conditions. At the first stage we made the reconstruction of stress-strain state in half-space after plastic surface hardening procedure based on partial information about distribution for one residual stress tensor co...

For the calculation of residual stresses and plastic strains in hollow and solid surface-hardened cylindrical specimens we suggest the mathematical models, which take into account both the cases of hardening leading to the isotropy (hydraulic shot blasting procedure) and to the anisotropy (roller burnishing process) of plastic strains in the surfac...

This paper presents an experimental and theoretical study of the influence of a tensile load on the relaxation of residual stresses in a hardened cylindrical specimen of ZhS6KP alloy under creep conditions at 800A degrees C. An experimental study was conducted to investigate the distribution of the axial residual stress tensor component across the...

The effect of thermoexposition on residual stresses and limiting amplitude of the stress cycle for M6 bolts made of 16KhSN steel having a rolled thread is examined. Based on the fatigue tests performed, it has been shown that the relationship between residual stresses in bolt cavities and limiting amplitude of bolt stress cycle is well illustrated...

Предложена двухслойная математическая модель шейки бедренной кости человека, армированной имплантатами различной конструкции, для моделирования напряжeнно-деформированного состояния, возникающего при хирургической методике профилактики переломов шейки бедра путeм принудительного введения металлических имплантатов. Приведены спроектированные констру...

The way of solution of the coupled boundary value problem of solid body deformation for the case of a plastically softening material is offered. The strain and stress fields obtained by the simulated undamaged construction behavior modeling under the action of fictitious forces are used as basic data for calculation. The equivalence of simulated un...

The boundary value problem of steady-state creep for thick-walled misaligned tube under internal pressure was considered. The approximate analytical solution of this problem by method of small parameter including the second approach is under construction. The solution for the state of plane deformation is constructed. The hypothesis of incompressib...

The method for calculating the boundary-value problem of the evaluation of kinetics of the stress-strain state of surface-hardened solid cylindrical specimen under creep for three types of stress state (tension, pure torsion, the combined effect of tensile load and torque) is offered. The energy theory of creep and creep rupture strength is used as...

Energy-type kinetic equations of inelastic rheological deformation are proposed in which the elastic, plastic, and creep strains are the additive components of the total strain, and the damage parameter is taken into account. A model of viscoelastic material with a creep kernel of exponential type is considered. The Lyapunov stability of solutions...

A method is proposed to study the distribution of residual stresses in a semicircular notch in a hollow cylindrical specimen after advanced surface plastic deformation. The initial information used in the method is one or two experimentally determined components of the residual stress tensor in the hardened layer of the smooth specimen. The problem...

An approximation method for the evaluation of the residual stress relaxation in face-hardened blades of gas turbine engines under creep is reported. A hypothesis that allows for the blade to be decomposed into the blade “body” and a thin hardened surface layer underlies this method, which enables one to divide the problem under consideration into a...

A non-linear steady-state creep stochastic boundary value problem is solved for a thick-walled tube acted upon by an internal pressure for the case of a plane strain state. It is assumed that the properties of the tube material are described by a random function of its radius. The constitutive creep relations are taken in accordance with non-linear...

A stochastic model of nonisothermal creep and long-term strength of metallic materials is proposed. Experimental data on the creep of the ZhS6KP alloy at temperatures equal to 900, 950, and 1000°C are stochastically analyzed. These experimental data are used to substantiate the hypotheses applied in constructing the model. The stochastic model is c...

A mathematical model for determining residual stress fields and plastic deformations in a hardened layer of a sample cylinder after anisotropic strengthening is described. A procedure is set forth and the model is identified on the example of sample cylinders made of 40XH steel after running with a roller. Experimental and calculation results are a...

A mathematical model is proposed for calculating the stress-strain state of a cylindrical specimen, which arises as a result of plastic surface hardening leading to material deformation anisotropy. The model adequacy is verified through comparisons with experimental data for cylindrical specimens made of 30KhGSA and St. 45 steels. A method of ident...

A direct method of solving a boundary-value problem for a surface-hardened cylindrical specimen affected by a tensile load under creep conditions is proposed. Relations for estimating the kinetics of the stress-strain state in the hardened layer are obtained. The adequacy of the solution is verified by experimental data on relaxation of residual st...

The solution of the non-linear stochastic boundary-value problem of the creep of a thin plate in a plane stress state when the elastic strains are small and can be neglected is presented. The plate material is stochastically inhomogeneous so that the stress and strain tensors are random functions of the coordinates. The constitutive creep relation,...

Calculation procedure of influence of temperature endurances on an increment of a fatique point for strengthened cylindrical specimen with pressure concentrators is proposed. In order to illustrate the method on modelling examples it is demonstrated that residual pressure relaxation leads to decrease in an increment of a fatique point of strengthen...

A mathematical model is proposed to describe the experimentally observed creep effect on the instantaneous elastic deformation of physically nonlinear elastic microinhomogeneous materials. Using a structural model of the medium, it is shown that, during unloading of a sample after creep at constant stress, the elastic strain can be both larger and...

An analytical method for the solution of two-dimensional nonlinear creep problems is developed using as an example the biaxial extension of a plane from a stochastically inhomogeneous material with damage accumulation and the third stage of creep taken into account. The governing creep relation is adopted in accordance with the energetic version of...

Two-dimensional, nonstationary heat-conduction problems in a system of four finite bodies with an internal mobile heat source of the first kind (burning front) have been solved by the finite-element method. The influence of basic technological factors on the temperature-field parameters in the process of synthesis of TiB-40% Ti alloys has been inve...

The physically and statistically nonlinear problem of steady-state creep for a thick-walled tube loaded by internal pressure is solved in the third approximation using the small-parameter method. The variances of random creep strain rates and displacements are calculated. The results obtained are compared with the solution of the same problem in th...

A uniaxial phenomenological energetic model for description of inelastic deformation and destruction of metals under a joint action of static and cyclic loads is proposed. The amplitude value of the cyclic component of stress in experiments was less than 10% of static loading. The model proposed was carefully verified in experiments with the ÉP742...

Stochastic rheological equations and an energy criterion of failure are proposed, making it possible to establish both the laws of distribution of inelastic deformation during creep and time for failure on the basis of the Monte Carlo method. A method of identifying stochastic and deterministic parameters of the model from the results of uniaxial t...

Stochastic rheological equations and the power criterion of failure are suggested which allow establishing both the distribution laws of inelastic deformation in the creep process and time to failure on the base of statistical tests of the Monte Carlo method. A procedure is developed for identification of random and determinate parameters of the mo...

The article suggests an energy alternative of the phenomenological rheological equations and criteria of failure of metals for a broad range of stresses including stresses higher than yield stress. The approach is based on the hypothesis that the damage to material is proportional to the linear combination of the work of true stress on creep strain...

The authors propose an energetic variant of phenomenological rheological equation and a criterion of the metals destruction in a wide range of stresses including those above the yield point. The approach is based on a hypothesis that a parameter of destructiveness of a material is assumed to be proportional to a linear combination of the acting str...