Analysis of the stress-strain state of copper M0B under different schemes of equal channel angular pressing and its effect on the structure and physical and mechanical properties

2019 ◽  
pp. 47-53
Author(s):  
L. F. Sennikova ◽  
G. K. Volkova ◽  
V. M. Tkachenko
Keyword(s):  
Equal Channel Angular Pressing ◽  
Strain State ◽  
Physical And Mechanical Properties ◽  
Strength Properties ◽  
Stress Strain ◽  
Loading Pattern ◽  
Stress Strain State ◽  
Angular Pressing ◽  
Fine Copper ◽  
Copper Structure

The results of studies of the stress-strain state of copper M0b after deformation under different schemes of equal channel angular pressing (ECAP) are presented. The level of macro and micro stresses in copper has been determined in various ECAP modes. It is shown that the strength properties, deformation porosity and parameters of the fine copper structure differ depending on the loading pattern.

scholarly journals Settlement and bearing capacity of water-saturated soils of foundations of finite width under static impact

Vestnik MGSU ◽  
2021 ◽  
pp. 463-472
Author(s):  
Zaven G. Ter-Martirosyan ◽  
Armen Z. Ter-Martirosyan ◽  
Ahmad Othman
Keyword(s):  
Bearing Capacity ◽  
Strain State ◽  
Water Saturation ◽  
Strength Properties ◽  
Finite Width ◽  
Stress Strain ◽  
Linear Deformation ◽  
Stress Strain State ◽  
Linear And Nonlinear ◽  
Water Saturated

Introduction. In case of brief exposure to static loads or dynamic loads, in conditions of absence of drainage, distribution of total stresses between the skeleton of soil and pore gas-containing water should be taken in account. The situation of the stress-strain state of the base is further complicated when we consider the degree of water-saturation of soil of the foundation (0.8 < Sr ≤ 1). The aim of the study is to pose and solve problem of the stress-strain state of a water-saturated soil massif, Including settlement and bearing capacity of a water-saturated base of a foundation of finite width, depending on the degree of water saturation of soils, taking into account the linear and nonlinear properties of the skeleton of soil and the compressibility of pore gas-containing water. Materials and methods. Henckyʼs system of physical equations are used as a calculation model to describe the relationship between deformation and stresses of soil, which takes into account the influence of the average stress on the deformation and strength properties of the soil. This system allows us to represent the linear deformation of the soil as the sum of the volumetric and shear components of the soil of this deformation. In addition allows us too to determine the deformation of the layer of soil, as part of the compressible thickness of the base of foundation with finite width under conditions of free deformations. Results. Depending on the linear and nonlinear deformation parameters, the settlement can be developed with a damped curve (S – p) and stabilize, and can be developed with a non-damped curve (S – p) and moved to the stage of progressive settlement. Conclusions. Solutions have been made for cases when the water-saturation of the base soils changes in the range of 0.8 to 1.0. It is shown that the settlement and bearing capacity of a water-saturated base significantly depends on the degree of water saturation of soils.

scholarly journals Predicting the Stress-Strain State of the Fractured Rock Massif on the Example of Interchamber Pillars

2019 ◽  
Vol 9 (2) ◽  
pp. 4228-4233
Keyword(s):  
Strain State ◽  
Numerical Models ◽  
Fractured Rock ◽  
Strength Properties ◽  
Rock Massif ◽  
Qualitative Description ◽  
Stress Strain ◽  
Stress Strain State ◽  
Geological Surveys ◽  
Spatial Geometry

The article describes the finding of the qualitative differences in the formation of the stress-strain state of a disturbed rock massif on the example of interchamber pillars with various methods of accounting for the structural disturbance and different spatial geometry of the cracks. Three numerical models are created with different methods of accounting for the disturbances in the massif continuity: in the first model, the strength of the massif is described by the Hoek and Brown criterion; the second and the third models are rock massifs for which violations in the continuity are formed explicitly, using ready-made templates of the systems of cracks presented in the Phase2 software product. The results obtained for the different models illustrate the inaccuracies occurring in assessing the disturbance of rock massif using score criteria. Models with underrated strength properties of the rock inaccurately describe the real mechanisms of the fractured massif: the qualitative description is not consistent with the results of field observations and geological surveys of rocks in general.

scholarly journals Application of a computational and experimental method of analysis the complexly stressed state of rubber membranes for effective solutions for their production

2021 ◽  
Vol 83 (2) ◽  
pp. 230-236
Author(s):  
D. V. Kudelin ◽  
T. N. Nesiolovskaya
Keyword(s):  
Stressed State ◽  
Experimental Method ◽  
Strain State ◽  
Physical And Mechanical Properties ◽  
Standard Test ◽  
Spherical Indenter ◽  
Bag Filter ◽  
Stress Strain ◽  
Rubber Membrane ◽  
Stress Strain State

The competitiveness of rubber membranes determined by their durability, quality, reliability, including the time required to create. During operation, the membranes undergo complex deformations, as a result of which a large number of potential destruction zones of a different nature arise, which can lead to the failure of the product. The standard test methods used in the development of formulations for membranes involve testing the material under uniaxial tension conditions in most cases and do not take into account the actual loading conditions of the product during operation, which significantly increases the development time of new formulations for membranes. The paper presents and applies in practice a computational and experimental method of analysis the complexly stressed state of rubber membranes, including carrying out simple laboratory tests in a heterogeneous complexly stressed state, which is realized during the operation of rubber membranes, and analyzing the stress-strain state by the finite element method. An inhomogeneous complexly stressed state was realized by forcing the rubber membrane with a spherical indenter. The application of a computational-experimental method for analyzing the complexly stressed state of rubber membranes is considered on the example of a rubber corrugated membrane of an automatic valve of a bag filter purge system. An assessment of the physical and mechanical properties of rubbers in a heterogeneous complexly stressed state was carried out, as well as an analysis of the stress-strain state of the membrane when it was loaded with a spherical indenter, which made it possible to identify the most dangerous zones of the section. The complex use of this method made it possible to improve the resource of this corrugated membrane by thirty five percent in comparison with the standard, while reducing the creation time.

scholarly journals About One of the Approaches for the Research of the Stress-Strain State of a Flange Connection with a Seal Made of an Alloy with Shape Memory

2022 ◽  
Author(s):  
A. Boikov
Keyword(s):  
Mechanical Properties ◽  
Shape Memory ◽  
Contact Zone ◽  
Axial Compression ◽  
Strain State ◽  
Physical And Mechanical Properties ◽  
Stress Strain ◽  
Flange Connection ◽  
Stress Strain State ◽  
Alternative Approach

Abstract. Design features of a flange connection with a seal made of an alloy with shape memory and the most commonly used methods of researching of the stress-strain state of such connections are estimated. Alternative approach for stress-strain state analysis is proposed, it is based on modeling of the contact zone of the sealing surfaces by means of an equivalent gap between the layers, the value of which changes during axial compression of the multilayer ring and goes into tension. Formulas for determining of contact stresses at the border of layers, which take into consideration the variable physical and mechanical properties of the materials of each layer are presented.

scholarly journals Determination of the safety factor of cement stone based on numerical modeling of the stress-strain state of the near-wellbore zone, taking into account the change in the elastic-strength properties of cement during its hardening and under the influence of an acid reagent

2021 ◽  
pp. 8-16
Author(s):  
S. N. Popov ◽  
Keyword(s):  
Finite Element ◽  
Numerical Modeling ◽  
Safety Factor ◽  
Strain State ◽  
Strength Properties ◽  
Cement Stone ◽  
Elastic Model ◽  
Stress Strain ◽  
Stress Strain State ◽  
Acid Reagent

The results of laboratory studies of the elastic-strength properties of cement stone samples depending on the hardening time and the effect of an acid reagent, and approximated dependences of the change in the elastic modulus, Poisson's ratio and strength properties, depending on the time characteristics for two types of plugging materials are presented. A finite element scheme of the nearwellbore zone has been developed, taking into account the cement stone and the production casing. The results of numerical modeling of the stress-strain state of columns with a diameter of 146 and 178 mm, cement stone and reservoir rocks near the well based on an elastic model are presented. The analysis of the stress field for the occurrence of zones of destruction in the cement stone using the Coulomb-Mohr criterion is carried out. It is shown that, depending on the time of hardening and the effect of an acidic reagent, cement does not collapse and retains a sufficient safety factor. Keywords: cement stone; plugging material; elastic-strength properties; near-wellbore zone; numerical model; finite element method; stress-strain state; safety factor.

КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ ОСОБЛИВОСТІ ХВОСТО-ВИХ БАЛОК СІТЧАСТОГО ТИПУ З ПОЛІМЕРНИХ КОМПО-ЗИЦІЙНИХ МАТЕРІАЛІВ ВЕРТОЛЬОТІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ

2020 ◽  
pp. 15-30
Author(s):  
А. Г. Гребеников ◽  
И. В. Малков ◽  
В. А. Урбанович ◽  
Н. И. Москаленко ◽  
Д. С. Колодийчик
Keyword(s):  
Finite Element ◽  
Strain State ◽  
Layer Structure ◽  
Metal Structure ◽  
Element Model ◽  
Stress Strain ◽  
Element Analysis ◽  
Mesh Structure ◽  
Stress Strain State ◽  
Mesh Structures

The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.

Sign in / Sign up

Export Citation Format

Share Document