Comparison of methods of stress-strain state estimation in the upset of a cylindrical workpiece

This paper aims to determine the effect of the sector radius of a workpiece-deforming tool on the stress-strain state in the center of elastoplastic deformation and residual stresses in the hardened zone of the surface layer of cylindrical workpieces. A mathematical model of local loading was constructed using the finite element method and AN-SYS software. This model was used to determine the values of temporary and residual stresses and deformations, as well as the depth of plastic zone, depending on the sector radius of the working tool. The simulation results showed that, under the same loading of a cylindrical surface, working tools with different sector radii create different maximum tempo-rary and residual stresses. An assessment of the stress state was carried out for situations when the surface layer of a product is treated by workpiece-deforming tools with a different shape of the working edge. It was shown that, compared to a flat tool, a decrease in the radius of the working sector from 125 to 25 mm leads to an increase in the maximum temporary and residual stresses by 1.2–1.5 times, while the plastic zone depth increases by 1.5–2.4 times. The use of a working tool with a flat surface for hardening a cylindrical workpiece ensures minimal temporary residual stresses, com-pared to those produced by a working tool with a curved surface. A decrease in the radius of the working sector leads to an increase in temporary residual stresses by 2–7%. The plastic zone depth ranges from 1.65 to 2.55 mm when chang-ing the sector radius of the working tool.

Download Full-text

Structure determination and composite wing spar stress-strain state estimation

MATEC Web of Conferences ◽

10.1051/matecconf/201712902040 ◽

2017 ◽

Vol 129 ◽

pp. 02040 ◽

Cited By ~ 1

Author(s):

Pavel Solovyev ◽

Andrey Gomzin ◽

Yuriy Pervushin ◽

Fanil Musin ◽

Sergey Galyshew

Keyword(s):

State Estimation ◽

Structure Determination ◽

Strain State ◽

Stress Strain ◽

Stress Strain State ◽

Wing Spar ◽

Composite Wing

Download Full-text

EVALUATION OF DEFORMABILITY OF MATERIAL OF PREPARATIONS DURING ROLLING

ENGINEERING, ENERGY, TRANSPORT AIC ◽

10.37128/2520-6168-2021-2-3 ◽

2021 ◽

pp. 22-30

Author(s):

Volodymyr Mikhalevich ◽

Viktor Matviychuk ◽

Iryna Bubnovska

Keyword(s):

Strain State ◽

Side Surface ◽

Cylindrical Sample ◽

Stress Strain ◽

Workpiece Material ◽

Cold Forming ◽

Engineering Software ◽

Stress Strain State ◽

Relative Compression ◽

Cylindrical Workpiece

The article presents the results of development and research of the technological process of cold forming rolling of aluminum billets. The main obstacle to the implementation of such processes is the danger of destruction of materials, which necessitated the study of the stress-strain state, plasticity and assessment of the deformability of the workpiece material. To experimentally determine the ductility of metals, a rolling method was developed, according to which the deformation of the free side surface of the cylindrical sample occurs under uniaxial tension. Increasing the degree of deformation and bringing the material to fracture is provided due to the increase in the radii of the rolls during rolling and deformation of the sample on the wedge. Analysis of the stress-strain state of the free side surface of the cylindrical workpiece was performed by the finite element method, which used a specialized engineering software package DEFORM 3D. As a result, a significant inhomogeneity of the stress-strain state in the deformation zone is established. The most severe stress state is observed on the free side surfaces of the workpiece, which causes the danger of its destruction in this area. The dependence between the relative compression of the workpiece during rolling and the intensity of deformation on its side surface is obtained, which allows to determine the limiting thickness of the workpiece before destruction. As a result of the assessment of the deformability of aluminum alloys during cold rolling, using the curves of limit deformations and the scalar criterion of deformation, the limits to the destruction of the intensity of deformation and the limit value of the relative compression of the workpiece. The use of constructed models makes it possible to determine the value of the used plasticity resource at intermediate stages of rolling.

Download Full-text

THE STRESS–STRAIN STATE ESTIMATION OF SLABS WITH SHEAR REINFORCEMENT ACCORDING TO ARMENIAN AND FOREIGN BUILDING CODES

Zeszyty Naukowe Politechniki Częstochowskiej Budownictwo ◽

10.17512/znb.2018.1.02 ◽

2019 ◽

Vol 174 (24) ◽

pp. 13-18

Author(s):

Hovhannes Avagyan ◽

Keyword(s):

State Estimation ◽

Strain State ◽

Building Codes ◽

Shear Reinforcement ◽

Stress Strain ◽

Stress Strain State

Download Full-text

RESEARCH OF INFLUENCE OF UNFINISHED CONSTRUCTION EXCAVATION ON STRESS-STRAIN STATE OF EXPLOITED BUILDING BEARING STRUCTURES

Building constructions. Theory and Practice ◽

10.32347/2522-4182.2.2018.3-12 ◽

2018 ◽

Vol 0 (2) ◽

pp. 3-12

Author(s):

A Banakh

Keyword(s):

Strain State ◽

Stress Strain ◽

Stress Strain State

Download Full-text

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

Open Information and Computer Integrated Technologies ◽

10.32620/oikit.2020.88.02 ◽

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.

Download Full-text