Effect of Pore Architecture of Titanium Implants on Stress-Strain State upon Compression

2017 ◽  
Vol 265 ◽  
pp. 606-610 ◽  
Author(s):  
Yu.N. Loginov ◽  
S.I. Stepanov ◽  
E.V. Khanykova
Keyword(s):  
Strain State ◽  
Titanium Implants ◽  
Stress Strain ◽  
Element Analysis ◽  
Stress Strain State ◽  
Area Reduction ◽  
Individual Unit ◽  
Unit Cells ◽  
Specific Configuration ◽  
Pore Cell

The problem of stress-strain state upon compression of implant of titanium alloy with cellular architecture was formulated by means of ABAQUS software and finite element analysis. The volume of the material was segmented on the unit cells characterized by specific configuration. The boundary conditions and physical equations were stated to describe the correlation between stresses and strains. The calculations of stress values, area reduction and mean stress were performed. The increased strain rates were revealed in horizontal pore cell walls. Joint simulating of several individual unit cells was provided. Zone seeing tensile stresses were observed in the segment of radius of the unit cell. The estimation of threatening sections location of the construction was conducted.

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.

scholarly journals Influence of the concrete strength and the type of supports on the stress-strain state of a hyperbolic paraboloid shell footbridge structure

2021 ◽  
Vol 17 (4) ◽  
pp. 379-390
Author(s):  
David Cajamarca-Zuniga ◽  
Sebastian Luna
Keyword(s):  
Thin Shell ◽  
Strain State ◽  
Concrete Strength ◽  
Design Parameters ◽  
Live Load ◽  
Structural Behaviour ◽  
Stress Strain ◽  
Hyperbolic Paraboloid ◽  
Element Analysis ◽  
Stress Strain State

Relevance. This work is the first in a series of publications on the selection of a suitable analytical surface for implementation as a self-supporting structure for a thin shell footbridge. The study on the influence of concrete strength, live load position and support types on the stress-strain state of a hyperbolic paraboloid (hypar) shell is presented. Objective - to define the initial design parameters such as the appropriate concrete strength and the support type that generates the best structural behaviour to perform the subsequent structural design of a thin shell footbridge. Methods. The static finite element analysis was performed for 4 compressive strengths of concrete (28, 40, 80, 120 MPa) which correspond normal, high and ultra-high resistance concrete, 5 different live load arrangements and 3 different support conditions. Results. The shell model with pinned (two-hinged) supports shows the same vertical displacements as the model with fixed supports (hingeless). For the studied shell thickness, in terms of stress behaviour, the model with pinned ends is more efficient. The combination of two-hinged supports with 80 MPa concrete strength shows a better structural performance.

Mathematical Simulation of Cramped Bending of Sheet Parts Using Finite Element Analysis

2016 ◽  
Vol 685 ◽  
pp. 186-190 ◽  
Author(s):  
Е.V. Eskina ◽  
E.G. Gromova
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Mathematical Simulation ◽  
Process Parameters ◽  
Strain State ◽  
Basic Process ◽  
Ansys Software ◽  
Stress Strain ◽  
Element Analysis ◽  
Stress Strain State

The paper describes the method of manufacture of profiles in cramped bending conditions using polyurethaneThe scope of studies included stress-strain state of elastic die and parent sheet, as well as the influence of the basic process parameters on characteristics of the produced items using ANSYS software.

Using FEM Analysis for Evaluating Lifetime of the Turbine Blades Repaired by Different Kinds of Titanium and Nickel Alloys

2008 ◽  
Vol 47-50 ◽  
pp. 37-40
Author(s):  
Aleksandrs Korjakins ◽  
Sergejs Gluhihs ◽  
Andrejs Popovs ◽  
Aleksandr Tiskunov
Keyword(s):  
Strain State ◽  
Turbine Blades ◽  
Fem Analysis ◽  
Laser Forming ◽  
Stress Strain ◽  
Element Analysis ◽  
Stress Strain State ◽  
Wide Range ◽  
Direct Laser ◽  
Attractive Option

With increasing attention being devoted to the problem of reducing service costs for a wide range of turbines and compressors, an attractive option is repair of damaged blades, instead of replacing them by new ones. A lot of different methods are used to repair blades and other parts of turbines and compressors. The processes of laser metal deposition (LMD) and direct laser forming (DLF) are modern methods used to repair blades made of titanium alloys. In the present study, the finite element analysis (FEM) has been applied to determine the stress-strain state of the repaired blades in service conditions. Different forms and sizes of the damaged zones have been analyzed. Several kinds of alloys, such as Incoloy 903, Carlson C800 and Inconel 718, appropriate for the LMD and DLF methods, have been utilized in repairing the blades. Two kinds of blades, with and without cooling hollows, have been examined. Lifetime of the repaired turbine has been evaluated by comparing the results obtained from the modal and stress-strain state analyses of the repaired and original parts. The results allow evaluating influence of sizes and forms of the damaged zones, as well as choice of the alloys applied, on lifetime of the repaired blades.

scholarly journals АНАЛІЗ НАПРУЖЕНО-ДЕФОРМОВАНОГО СТАНУ ФІТИНГОВОГО СТИКУ ПАНЕЛЕЙ ВІД'ЄМНОЇ ЧАСТИНИ КРИЛА ТА ЦЕНТРОПЛАНА ТРАНСПОРТНОГО ЛІТАКА

2021 ◽  
pp. 97-112
Author(s):  
Yifang Sun ◽  
А. А. Вендин
Keyword(s):  
Strain State ◽  
Maximum Stress ◽  
Solid Model ◽  
Force Distribution ◽  
Maximum Strain ◽  
Stress Strain ◽  
Element Analysis ◽  
Wing Section ◽  
Stress Strain State ◽  
Center Section

Fitting joints are widely used in aircraft structures, and they are responsible for the interconnection of important components. The stress-strain state analysis of the fitting joint must be carried out before the performance analysis of the fitting joint. With the help of 3D modeling software (CATIA) and finite element analysis software (ANSYS), the stress-strain state of each component in the fitting joint of outer wing section was calculated in this paper. In the CATIA, the solid model is simplified and segmented according to the size of the cross section and the height of the center of gravity of the model. In the ANSYS, the beam elements are used to replace the simplified segmented model to obtain the internal force distribution of the solid model and to determine the magnitude and change law of the stress applied to the end of the solid model. When calculating the force transmitted by the fastener, the pre-tightening force of the bolt and the interaction between the surfaces of the component are taken into account, so as to simulate the real force situation well. Therefore, it is a very feasible method to use the CATIA and ANSYS to obtain the stress-strain state of components in the fitting joint of center wing section and outer wing section.The results show that under the working conditions of the fitting joint (130Mpa), the fitting of outer wing section with center section has a maximum stress of 245.79Mpa and a maximum strain of 0.0035, the stringer of outer wing section has a maximum stress of 293.17Mpa and a maximum strain of 0.0047, the lower panel of outer wing section has a maximum stress of 289.53Mpa and a maximum strain of 0.0042. The connecting bolts (M8 and M6) have a maximum stress of 686.81Mpa and a maximum strain of 0.0063, which meets the design requirements. In addition, according to the analysis results of the stress-strain state of the fitting joint of outer wing section, the force distribution of the bolts in the fitting joint of outer wing section with center section was obtained in this paper. It has been confirmed that due to the different positions and force areas of the bolts, the force distribution between rows of bolts is uneven, and the first row of bolts has a more force.

Assessment of the Stress-Strain State of a Tube Sheet of the Heat Exchanger at Rotary Friction Welding Application

2020 ◽  
Vol 991 ◽  
pp. 70-76
Author(s):  
Andrey Sergeevich Tokarev ◽  
Denis Vladimirovich Karetnikov ◽  
Rif Garifovich Rizvanov ◽  
Ayrat Minnulovich Fayrushin ◽  
Mars Zul'fatovich Zaripov
Keyword(s):  
Friction Welding ◽  
Strain State ◽  
Geometric Model ◽  
Tube Sheet ◽  
Special Equipment ◽  
Stress Strain ◽  
Element Analysis ◽  
Stress Strain State ◽  
Rotary Friction Welding ◽  
State Models

The aim of the study described in this paper is to assess the effect of forces acting on the tube sheet during friction welding on the stress-strain state of the tube sheet.For this, we calculated the stresses and displacements arising in the tube sheet during friction welding. The calculations were carried out in the ANSYS (finite element analysis software package). To carry out the calculations, solid-state models of tube sheets with diameters of 400, 600, 800, 1000, 1200, 1400 mm and thicknesses of 30, 40, 50, 60, 70 mm were created. The diameter of the holes for the heat exchange tubes was chosen equal to 25 mm, the holes are placed on the vertices of an equilateral triangle with a step equal to 32 mm. Then, based on geometric models, grids of 8-node finite elements were created. The calculation model takes into account the symmetry of the geometric model and the character of loading relative to the YZ and XZ planes. The material used was steel with a Poisson's ratio of 0.3 and an elastic modulus of 2,11·105 MPa.As a result of the calculations, it was found that as a result of the action of force factors during friction welding, significant stresses and deformations arise in the tube sheet. The greatest values of deflection and stresses occur in the central sector of the tube sheet in the area of application of force. In this case, the zone of maximum stresses is significantly localized: they are concentrated around the central hole, and movements smoothly increase from the periphery to the center of the tube sheet.The value of this study is that it allowed to determine the need to use special equipment that increases the local stiffness of the tube sheet sector subjected to friction welding.

scholarly journals RESEARCH OF THE STRESS-STRAIN STATE OF THE MAIN CYLINDER OF THE HYDRAULIC PRESS

2019 ◽  
pp. 59-67
Author(s):  
Serhii Nemchynov ◽  
Illya Nachovnyy ◽  
Alexander Khristenko ◽  
Vasyl Babenko
Keyword(s):  
Finite Element ◽  
Strain State ◽  
Hydraulic Press ◽  
Stress Strain ◽  
Element Analysis ◽  
Equivalent Stresses ◽  
Stress Strain State ◽  
Wide Range ◽  
Bottom Zone ◽  
Distribution Of Stresses

In the article the stress-strain state of the main cylinder of the hydraulic press for the manufacturing of large-sized plastic products has been investigated using software of finite-element analysis. It is established that the stress-strain state is characterized by a general and local uneven distribution of stresses and displacements. The nature of the distribution of stresses, deformations, displacements, safety factors along the length of the cylinder allowed conditionally divide the cylinder into three characteristic zones: flange zone, Lame zone, bottom zone. In each of the zones we found the areas in which the maximum stresses and strains are observed. It was found that the maximum equivalent stresses calculated according to the Huber-Mises energy theory of strength are observed on the inner surface of the cylinder, and in their fillets in the zones of the bottom and flange. A comparative analysis of the stresses and displacements determined by the Lame formulas and the finite element method showed that in the Lame zone their values do not change significantly. Studies on the influence of the radius, which varied over a wide range, and the fillet angle, made it possible to establish the region of maximum principal and equivalent stresses and reduce their magnitude. The calculations revealed the fillet region in which the axial tensile stresses act and determine the fillet angle at which the axial stresses are equal in magnitude and sign The study allowed to change the geometry of the cylinder, reduce the stress in the cylinder fillet and its weight. The results of the study can be applied to improve the existing and design of new hydraulic presses of the chemical industry, as well as the basis for further research.

Microgeometrical characteristics of electrospark coatings in the initial state

2020 ◽  
Vol 98 (4) ◽  
pp. 33-39
Author(s):  
V. Tokaruk ◽  
◽  
O. Mikosianchyk ◽  
R. Mnatsakanov ◽  
N. Rohozhyna ◽  
...  
Keyword(s):  
Strain State ◽  
Normal Load ◽  
Base Material ◽  
Arithmetic Mean ◽  
Surface Plastic ◽  
Initial State ◽  
Stress Strain ◽  
Element Analysis ◽  
Electrospark Coating ◽  
Stress Strain State

Microgeometric parameters of the effect of discrete electrospark coatings on their stress-strain state have been evaluated for the case of using a combined technology of modification of duralumin D16, which includes the technique of electrospark alloying with subsequent surface plastic deformation of coatings formed. According to the profilograms of discrete electrical coatings, the curves of the bearing surface (Abbott curves) were constructed and the parameters that drastically affect tribological characteristics of the coatings were determined. It was shown that modification of duralumin D16 with a combined electrospark coating VK-8 + Cu reduces the arithmetic mean height of peaks in the top portion of the profile by 4.4 and 3.2 times, doubles the arithmetic mean depth of the profile core irregularities, increases the arithmetic mean depth of profile valleys by 1.8 and 1.1 times, in comparison with electrospark coatings from hard alloy VK-8 and copper, respectively. These parameters help to reduce the period of running-in of the contact surfaces strengthened by the combined electrospark coating VK-8 + Cu, increase their bearing capacity, contact durability and specific oil consumption. On the basis of the finite element analysis method of the Nastran software complex, a model of the stress-strain state of a discrete coating/base was designed and distribution of the main normal stresses was determined for a coating compactness of 60% under a normal load of 600 N. The performed modeling revealed advantages of a combined technology for formation of wear-resistant electrospark coatings, which consists in turning residual tensile stresses into compressive ones. When modifying the duralumin D16 with a VK-8 + Cu coating, on the coating surface and in the base material, compressive stresses (-93 MPa and -20 MPa, respectively) are formed, which provides a decrease in wear of the modified surface by two times compared to unmodified duralumin D16.

Computer Simulation and Study of the New Forging Technology of Billets in a Step-Wedge Dies

2020 ◽  
Vol 299 ◽  
pp. 699-704
Author(s):  
Andrey O. Tolkushkin ◽  
Sergey N. Lezhnev ◽  
A.B. Naizabekov
Keyword(s):  
Computer Simulation ◽  
Comparative Analysis ◽  
Strain State ◽  
Drawing Process ◽  
Stress Strain ◽  
Stress Strain State ◽  
Specific Configuration

The paper presents the results of a computer simulation of the drawing process in the step-wedge dies of two configurations: with wedge-shaped protrusions in the first and second sections of the top and bottom dies, and with a wedge-shaped protrusion in the first and second sections of the top die and wedge-shaped cavity in the first and second sections of the bottom die. A comparative analysis of the stress-strain state and energy-power parameters is carried out. Based on the analysis conclusions about the feasibility of choosing a specific configuration of step-wedge dies depending on the set aim were made.

Stress–Strain State Prediction of High-Temperature Turbine Single Crystal Blades Using Developed Plasticity and Creep Models

2014 ◽  
Author(s):  
Boris Vasilyev
Keyword(s):  
Single Crystal ◽  
Strain State ◽  
Elastic Anisotropy ◽  
Inelastic Strain ◽  
Creep Model ◽  
Stress Strain ◽  
Element Analysis ◽  
Suggested Approach ◽  
Stress Strain State ◽  
Novel Approach

This paper discusses a novel approach to calculating inelastic strain that incorporates elastic anisotropy in combination with ANSYS finite element analysis (FEA) software to predict the stress–strain state kinetics of a single crystal (SX) nickel-based turbine blade. The approach is based on using “equivalent direction” and allows us to correctly define the critical load value and plastic strain field in SX details for different load types. The suggested approach is simple and generic and requires only a few standard experimental material properties. This should allow for an easy transition to actual blade design application. Predictions of plastic field distribution obtained using the suggested approach with anisotropic specimens are compared with experimental data as well as with the results obtained using a crystallographic approach. Good correlation was achieved. The second goal of this study is to develop a physically based, readily implementable creep model SX superalloy that accurately represents the creep phenomena of these materials under complex, thermomechanical loading conditions.

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