scholarly journals The Assessment of the Residual Stresses Influence on Generation of the Infringement in Shape-Complex Supporting Members

2019 ◽  
Vol 69 (1) ◽  
pp. 85-96
Author(s):  
Miroslav Pástor ◽  
Peter Čarák ◽  
Imrich Gömöry

AbstractThe aim of the paper is to assess the effect of residual stresses on the damage of the slide bearer. To quantify the residual stresses, the drilling method using SINT MTS 3000 drilling machine was chosen. The tensometric rosette application areas were determined based on the analysis of the results obtained by numerical modeling using the finite element method. Experimental measurement was performed on one unused slide bearer and on the other one, which during its present operation had completed about 9.106cycles. At the end of the paper, the analysis of the measured residual stress values in chosen locations is presented.

1993 ◽  
Vol 115 (4) ◽  
pp. 417-423 ◽  
Author(s):  
Y. Ueda ◽  
M. G. Yuan

The source of residual stresses in the vicinity of a weld may be expressed in terms of inherent strains. The characteristics of the inherent strain distributions in butt welds are investigated. It is found that the patterns vary little with changes in the welding conditions and sizes of the welded plates. With some assumptions, simple formulas are derived for the distribution and magnitude of inherent strain in a butt weld. A method of predicting the residual stress in a butt-welded plate using the characteristics of inherent strain distributions is presented. The validity of the method is confirmed by thermal elasto-plastic analysis using the finite element method (FEM).


The non-uniform thermal expansion and contraction resulting from welding processes cause residual stresses and strains. Experimental studies on measuring welding residual stresses and strains of structure are costly and sometimes they are not possible. Previously, analytical methods with idealized models were developed to determine the welding residual stresses and strain. Recently, numerical methods are constructed to analyze the stresses and the strains in welded structures. This paper presents the calculation results of residual stress and welding strain in butt welded joint of S355J2G3 carbon steel of 5 mm thickness made by MAG welding process with a single pass. The calculation is performed by two methods: the imaginary force method and the finite element method. In the finite element method, the SYSWELD software is used to simulate and to determine residual stresses and strain of this welded joint. The results of finite element method are compared with those of imaginary force method to show the rationality and the advantages of finite element method. The study results have shown that in this welded joint, only the longitudinal and transverse stress components are important and the other stress components are negligible.


1973 ◽  
Vol 95 (1) ◽  
pp. 283-291 ◽  
Author(s):  
C. H. Lee ◽  
H. Iwasaki ◽  
S. Kobayashi

Three problems, namely, autofrettage process, plastic upsetting of a solid cylinder, and plane-strain and axisymmetric extrusion, are treated for residual stress calculation. A thick-walled cylinder consisting of two loosely fitted concentric cylinders of different materials is subjected to various levels of internal pressure. The residual stresses were calculated with an emphasis on the case where the inner surface of the cylinder yields again upon removal of the internal pressure. Comparison between the calculations and the measurements is given. The residual stresses in plastic upsetting of a solid cylinder were calculated by the finite-element method. An attempt was also made to simulate the real situation in extrusion by the finite-element method. An estimation of the residual stress distribution is then discussed for axisymmetric extrusion problems.


2005 ◽  
Vol 490-491 ◽  
pp. 53-61 ◽  
Author(s):  
Dimitrios Elias Katsareas ◽  
Anastasius Youtsos

Dissimilar metal welds are commonly found in the primary piping of pressurized water nuclear reactor power plants. The safety assessment practice for such welds requires residual stresses to be taken into consideration. In the present paper the finite element method is utilized for the simulation of the welding process and prediction of the residual stress field in a dissimilar metal weld pipe joint. Although it is common practice to develop in-house finite element codes for weld simulation, the ANSYS commercial finite element code is selected. This is mainly due to the fact that industry focuses on commercial software, since residual stress analysis procedures based on them can be readily transferred to industrial applications. A simplified 2-D axi-symmetric model, in which residual stresses are produced due to the thermo-mechanical properties mismatch during cooling of the weld, is compared with a detailed model in which the complete multi-pass welding procedure is simulated. The latter incorporates the “birth & death of elements” technique, temperature dependant material properties and kinematic hardening material behavior. The aim of this comparison is to establish the degree of model detail and complexity, necessary to obtain satisfactory results and consequently to define a golden rule between computational cost and practically accurate predictions. Identifying the specific simulation parameters and variables, that have the highest impact on the accuracy of the computed results, is also important. It is concluded that, a bead-by-bead or lump-by-lump detailed simulation is necessary in order to obtain reasonably accurate residual stresses that cannot be predicted by a simplified model. A general conclusion is that the proposed method, being simple in implementation and cost effective concerning model complexity and analysis time, is a potential weld residual stress prediction tool.


2021 ◽  
Vol 11 (11) ◽  
pp. 5170
Author(s):  
Marek Krawczuk ◽  
Magdalena Palacz

Modern engineering practice requires advanced numerical modeling because, among other things, it reduces the costs associated with prototyping or predicting the occurrence of potentially dangerous situations during operation in certain defined conditions. Different methods have so far been used to implement the real structure into the numerical version. The most popular have been variations of the finite element method (FEM). The aim of this Special Issue has been to familiarize the reader with the latest applications of the FEM for the modeling and analysis of diverse mechanical problems. Authors are encouraged to provide a concise description of the specific application or a potential application of the Special Issue.


Author(s):  
Я.Б. Немировский ◽  
И.В. Шепеленко ◽  
С.Е. Шейкин ◽  
Ю.А. Цеханов ◽  
Ф.Й. Златопольский ◽  
...  

Разработан алгоритм и проведена оценка прочности сборных твердосплавных элементов со сплошной и дискретной рабочими поверхностями. Получены зависимости, позволяющие установить связь между конструктивными параметрами сборных деформирующих инструментов и их прочностью. Выполнены прочностные расчеты деформирующего инструмента для обработки отверстий значительного диаметра со сплошной и дискретной рабочими поверхностями. Численным моделированием, методом конечных элементов получены распределения эквивалентных напряжений в элементах инструмента и контактных напряжений по поверхности контакта твердосплавная вставка-корпус, что позволило проанализировать прочность инструмента под нагрузкой. Определены конструктивные параметры инструмента и приведены алгоритмы последовательности расчета сборных деформирующих элементов (ДЭ). Разработан алгоритм последовательности расчета сборного ДЭ для дискретного протягивания. Предложенная конструкция сборного рабочего элемента позволяет не только улучшить обрабатываемость изделия резания, но и уменьшить расход остродефицитного твердого сплава по сравнению с твердосплавным ДЭ аналогичных размеров на 6 кг. Полученные результаты можно использовать в инженерных расчетах при проектировании сборного инструмента для дискретного деформирования, а также для оценки прочности сборных инструментов, например, фрез, зенкеров, разверток при уточнении внешних нагрузок We developed an algorithm and assessed the strength of prefabricated carbide elements with solid and discrete working surfaces. We obtained dependencies that make it possible to establish a relationship between the design parameters of prefabricated deforming tools and their strength. We performed strength calculations of the deforming tool for machining holes of significant diameter with solid and discrete working surfaces. We obtained the distributions of equivalent stresses in the elements of the tool and contact stresses over the contact surface of the hard-alloy insert - body by numerical modeling, by the finite element method, which made it possible to analyze the strength of the tool under load. We determined the design parameters of the tool and here we give algorithms for the sequence of calculation of prefabricated deforming elements (DE). We developed an algorithm for the sequence of calculating the prefabricated DE for discrete broaching. The proposed design of the prefabricated working element allows not only to improve the machinability of the cutting product but also to reduce the consumption of an acutely deficient hard alloy in comparison with a hard alloy DE of similar dimensions by 6 kg. The results obtained can be used in engineering calculations when designing a prefabricated tool for discrete deformation, as well as for assessing the strength of prefabricated tools, for example, cutters, countersinks, reamers when specifying external loads


Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4842
Author(s):  
Huanping Yang ◽  
Wei Zhuang ◽  
Wenbin Yan ◽  
Yaomian Wang

The nanoindentation loading response of elastoplastic materials was simulated by the finite element method (FEM). The influence of the Young’s modulus E, yield stress σy, strain hardening exponent n and Poisson’s ratio ν on the loading response was investigated. Based on an equivalent model, an equation with physical meaning was proposed to quantitatively describe the influence. The calculations agree well with the FEM simulations and experimental results in literature. Comparisons with the predictions using equations in the literature also show the reliability of the proposed equation. The investigations show that the loading curvature C increases with increasing E, σy, n and ν. The increase rates of C with E, σy, n and ν are different for their different influences on the flow stress after yielding. It is also found that the influence of one of the four mechanical parameters on C can be affected by the other mechanical parameters.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Rachid Radouani ◽  
Mohamed Essahli ◽  
Younes Ech-Charqy

PurposeValidate the resistance of bolted connections in terms of stresses, resistant moment and contact pressure.Design/methodology/approachFinite element modeling of corroded bolted joint.FindingsThe three types of corroded assemblies are resistant to the applied loads.Originality/valueThe research is original, it studies the stress corrosion cracking of a bolted assembly's end plate by the finite element method.


Author(s):  
Chaodi Li ◽  
Ying Wang ◽  
James J. Mason

Bone cements are widely used to fix prostheses into bones for joint arthroplasty. During cement curing in total hip arthroplasty, residual stresses are introduced in the cement mantle. A finite element method was developed to predict such residual stress built-up. The effects of curing history on the residual stress distribution were investigated. Results showed that the predictions of the residual stresses agreed with the experimental tests very well. The residual stress build-up was shown to depend on the curing history. By preheating the prosthesis stem prior to implantation, a desired low level residual stress at the critical interface was obtained.


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