Journal articles: 'Strains and stresses – Analysis'

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Hyde, T. H., R. Sabesan, and S. B. Leen. "Approximate Prediction Methods For Multiaxial Notch Stresses and Strains Under Elastic-Plastic and Creep Conditions." Journal of Strain Analysis for Engineering Design 40, no. 6 (August 1, 2005): 535–48. http://dx.doi.org/10.1243/030932405x16016.

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This paper describes general techniques for predicting multiaxial notch stresses and strains under elastic-plastic and creep conditions. The Neuber method, which is often used in elastic-plastic analysis, has been adapted and extended for predicting creep equivalent notch stresses and strains, based on a time-stepping integration scheme. A linear interpolation method, often used in creep analysis, is adapted and extended for predicting elastic-plastic equivalent stresses and strains. Then notch principal stresses and strains are obtained by applying plasticity theory in combination with assumptions concerning the ratios of the stress or strain components. The accuracy of the predicted equivalent and principal stress and strain values are assessed by comparing predictions based on them with results obtained from finite element analyses.

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Korsunsky, A. M. "Eigenstrain analysis of residual strains and stresses." Journal of Strain Analysis for Engineering Design 44, no. 1 (December 16, 2008): 29–43. http://dx.doi.org/10.1243/03093247jsa423.

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Ghasemi Nejhad, Mehrdad N., Chiling Pan, and Hongwei Feng. "Intrinsic Strain Modeling and Residual Stress Analysis for Thin-Film Processing of Layered Structures." Journal of Electronic Packaging 125, no. 1 (March 1, 2003): 4–17. http://dx.doi.org/10.1115/1.1512295.

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Residual stresses develop due to intrinsic and extrinsic strains that form during the processing. Extrinsic strains can be determined using coefficient of thermal expansion, material properties, and processing conditions. An “Equivalent Reference Temperature (ERT)” technique is described and used to model and evaluate the intrinsic strains. piezoelectric microelectromechanical systems (P-MEMS) are considered in this work. Laminate theory with three-dimensional state of stress and strain is used to evaluate residual stresses using the ERT model. In finite element analysis (FEA), the residual stresses and strains of multi-layer P-MEMS structures deposited layer-by-layer during processing, are simulated using the “element birth-and-death” approach. The evaluated residual stresses for a simplified geometry using ANSYS three-dimensional FEA and analytical analysis employing three-dimensional laminate theory are presented along with their corresponding experimental results. A user-friendly software based on the 3-D laminate theory is developed and installed on the Internet. The “equivalent reference temperature” as well as residual stresses and strains can be determined using this software. The level of residual stresses and strains of P-MEMS depend upon various factors such as geometrical design, material selection, and process conditions.

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Xie, Jian Feng. "Finite Element Analysis on Stress and Strain of Protected Fiber Bragg Grating." Advanced Materials Research 148-149 (October 2010): 1639–42. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1639.

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The stresses and strains on the protected FBG and protected layer under varied temperature were analyzed in theory. In order to verify the theoretical analysis of stress and strain,a finite element analysis software(ANSYS) was used to simulate the stresses and strains on the protected FBG and protected layer. Both simulation and theoretical analysis are show that the strain and stress on protected layer in r direction decreases with the increasing of radius(r), while the strain and stress in direction increases with the increasing of radius(r) . The results of theoretical analysis matches the ones form simulations well.

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Zhang, Min, and Xitian Tian. "Residual stresses and strains analysis in press-braking bending parts considering multi-step forming effect." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 234, no. 4 (November 1, 2019): 788–800. http://dx.doi.org/10.1177/0954405419883053.

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Press-braking bending is a multi-step bending process and widely applied in the aerospace industry. Residual stresses and strains generated during the forming process play an important role in determining its forming parameters and bending path. This work aims to analyze the residual stresses and strains in press-braking bending parts using both the theoretical method and numerical method. First, the analytical model of residual stress and strain is established based on the elastic–plastic bending theory. Second, a fully finite element model of press-braking bending has been developed, and a procedure to simulate the multi-step bending process is presented by using the elastic–plastic large deformation finite element method. The simulation results are then compared with three-point bending experiments in terms of forming force and final shapes of the bent specimens, and excellent agreement is achieved. Finally, the results calculated from the analytical model are compared with the numerical results. The distributions of residual stresses and strains on the finished plate along the length and thickness direction, and particularly the multi-step forming effect on residual stresses and strains, are discussed. It is found that the residual stresses and strains decrease at the initial loading position along the thickness direction during the forming process of subsequent loading positions. With the same punch displacement, the residual stresses and strains at the initial loading position are less than those at the subsequent bending position.

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Xie, Jian Feng. "Finite Element Analysis on Stress and Strain of Embedded Fiber Bragg Grating." Advanced Materials Research 148-149 (October 2010): 1634–38. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1634.

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After FBG was protected and embedded into cement mortar, the stresses and strains on the FBG ,protected layer and cement mortar under varied temperature were analyzed in theory. In order to verify the theoretical analysis of stress and strain,a finite element analysis software(ANSYS)was used to simulate the stresses and strains on the FBG ,protected layer and cement mortar. The results of theoretical analysis matches the ones form simulations well.

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Klochkov, Yuriy V., Anatoliy P. Nikolaev, Tatiana A. Sobolesvskaya, and Mikhail Yu Klochkov. "Comparative Analysis of Plasticity Theory Algorithms in Finite-Element Calculations of the Rotation Shell." Materials Science Forum 974 (December 2019): 608–13. http://dx.doi.org/10.4028/www.scientific.net/msf.974.608.

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Comparative analysis of the use of the defining equations of plasticity theories obtained at the loading step in three ways is performed. In the first method, the relations between strains increments and stresses increments are obtained by differentiating the governing equations of the small elastic-plastic deformations theory between full stresses and strains. In the second method, the authors based on the proportionality hypothesis between the component deviators of strains increments and the component deviators of stresses increments without separating the incremental strain into elastic and plastic parts obtain the determining equations at the loading step. In the third method, the relations between the incremental strain and the stresses increment of the plastic flow theory are used on the basis of the hypothesis about the proportionality of the plastic deformations increments to the components of the stress deviator. Based on the analysis of algorithms for obtaining the constitutive relations and the analysis of the numerical results of the calculation example, preference is given to the second method of obtaining expressions between stress increments and strain increments without separating the latter into elastic and plastic parts.

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Xie, Jian Feng. "Finite Element Analysis on Stress and Strain of Nickel Electroless Plated Fiber Bragg Grating." Advanced Materials Research 383-390 (November 2011): 3893–97. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.3893.

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After FBG was nickel electroless plated, the stresses and strains on the FBG and nickel eclectroless plated layer under varied temperature were analyzed in theory. In order to verify the theoretical analysis of stress and strain,a finite element analysis software(ANSYS) was used to simulate the stresses and strains on the FBG and nickel ececltroless plated layer. The results of theoretical analysis matches the ones form simulations well.

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Safari, Maedeh, Shahrokh Shojaei, Pedram Tehrani, and Alireza Karimi. "A patient-specific finite element analysis of the anterior cruciate ligament under different flexion angles." Journal of Back and Musculoskeletal Rehabilitation 33, no. 5 (September 17, 2020): 811–15. http://dx.doi.org/10.3233/bmr-191505.

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BACKGROUND: The main responsibility of the anterior cruciate ligament (ACL) is to restore normal knee kinematics and kinetics. Although so far different research has been carried out to measure or quantify the stresses and strains in the ACL experimentally or numerically, there is still a paucity of knowledge in this regard under different flexion angles of the tibiofemoral knee joint. OBJECTIVE: Understanding the stresses and strains within the ACL under various loading and boundary conditions may have a key asset for the development of an optimal surgical treatment of ACL injury that can better restore normal knee function. This study aimed to calculate the stresses and strains within the ACL under different flexion angles using a patient-specific finite element (FE) model of the human tibiofemoral knee joint. METHODS: A patient-specific FE model of the human tibiofemoral knee joint was established using computed tomography/magnetic resonance imaging data to calculate the stresses and strains in the ACL under different flexion angles of 0, 10, 20, 30, and 45∘. RESULTS: Although the role of the flexion angle in the induced stresses and strains of the ACL was insignificant, the highest stress and strain were observed at the flexion angle of 0∘. The concentration of the stresses and strains regardless of the flexion angles were also located at the proximal end of the ACL, where the clinical reports indicated that most ACL tearing occurs there at the femoral insertion site. CONCLUSIONS: The results have implications not only for understanding the stresses and strains within the ACL under different flexion angles, but also for providing preliminary data for the biomechanical and medical experts in regard of the injuries which may occur to the ACL at relatively higher flexion angles.

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Glinka, G., W. Ott, and H. Nowack. "Elastoplastic Plane Strain Analysis of Stresses and Strains at the Notch Root." Journal of Engineering Materials and Technology 110, no. 3 (July 1, 1988): 195–204. http://dx.doi.org/10.1115/1.3226037.

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For the evaluation of the local elastoplastic strains and stresses at the notch root suitable approximation formulas of sufficient accuracy are often used. In the present study the “equivalent strain energy density” concept for elastic-plastic notch strain-stress analysis has been developed. It was found that the evaluation of the strain energy density in the notch tip plastic zones does not require any input data other than the material stress-strain relation and the elastic stress concentration factor. The concept was verified on the basis of the results obtained from plane strain elastic-plastic finite element analysis using the material model after Mro´z. Comparison of the two sets of results revealed satisfactory accuracy of the equivalent strain energy concept. It was also shown that all stress and strain components in the notch tip can be calculated by complementing the method with Hencky’s equations. Neuber-based calculations were also included in the study. It was found that the energy concept was superior to Neuber’s rule, especially in the presence of high inelastic strains in the notch tip.

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Bhatnagar, N. S., Pradnya Kularni, and V. K. Arya. "Primary Creep Analysis of an Anisotropic Thick-Walled Spherical Shell." Journal of Pressure Vessel Technology 109, no. 3 (August 1, 1987): 347–51. http://dx.doi.org/10.1115/1.3264876.

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The problem of primary creep of an orthotropic thick-walled spherical shell under internal pressure has been analyzed in this paper. The creep stresses and strains have been calculated using a method of successive approximations. All results have been obtained in nondimensional form. Effect of anisotropy on stresses and strain rates is discussed.

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Ezeilo, A. N., and G. A. Webster. "Neutron diffraction analysis of the residual stress distribution in a bent bar." Journal of Strain Analysis for Engineering Design 35, no. 4 (May 1, 2000): 235–46. http://dx.doi.org/10.1243/0309324001514387.

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A well-characterized residual stress distribution resulting from four-point bending has been analysed using the neutron diffraction technique. Residual stresses were obtained from the strains measured at discrete positions through the bent bar on the (111) and (311) crystal planes of a nickel-based alloy using the appropriate diffraction elastic constants. In addition a profile refinement method was used to determine the residual stresses from average strains from all the diffraction peaks in the spectrum. The measured residual stress profiles have also been compared with strain gauge data and with analytical and finite element predictions. It has been established that the profile refinement approach gives stresses which most closely match those obtained by the non-diffraction techniques.

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Lau, J. H. "Thermal Stress Analysis of SMT PQFP Packages and Interconnections." Journal of Electronic Packaging 111, no. 1 (March 1, 1989): 2–8. http://dx.doi.org/10.1115/1.3226505.

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An elasto-plastic analysis of the thermal stresses and strains in a surface mounted plastic-quad-flat-pack (PQFP) assembly by using a 3-D finite element method is presented in this paper. Detailed stress and strain distributions and whole-field displacements of the assembly are also provided for a better understanding of its mechanical behavior during thermal cycling. It was found that the stresses and strains in the PQFP solder joint are smaller than those in the plastic-leaded-chip-carrier (PLCC) solder joint. The results presented herein should be useful in the design for reliability of this class of surface mount assemblies.

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Li, Hong, and Hui Long Ren. "Welding Behavior Analysis of Stiffened Stainless Steel Structure." Key Engineering Materials 385-387 (July 2008): 413–16. http://dx.doi.org/10.4028/www.scientific.net/kem.385-387.413.

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Welding residual plastic strains and residual stresses are the product of complicated nonlinear behaviors of the structures during welding. The residual strains and stresses for stiffened stainless steel structure and welding fatigue analysis are studied in this paper. The three-dimensional transient temperature field is analyzed by FEM first. Doing the welding experiment for fundamental model is to verify the numerical results, the infrared thermograph is used to follow and record the whole process. The results of FEM are supported by experimental data. Then, the elastic-plastic-model is established to analyze the residual strains and stresses. Based on the stresses, loading and fatigue factors, according to Miner fatigue damage law, some fatigue behaviors such as fatigue life and remaining life are obtained.

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15

Ogawa, Masaru. "Proposal of an Eigen-Strain Estimation for Determination of Residual Stresses Considering the Influence of Machining." Advanced Materials Research 891-892 (March 2014): 1225–30. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.1225.

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In order to assure structural integrity for mechanical structures, it is indispensable to estimate three-dimensional residual stresses quantitatively to asses a crack growth rate of an observed crack. Now, the neutron diffraction method and the DHD (Deep Hole Drilling) method have been proposed to evaluate stress gradient in the thickness direction. However, estimated stresses by these methods can not be input to the FEM (Finite Element Method) model that has been widely used at design time for the assessment of the structural integrity. Then, the eigen-strain method has been proposed. In this method, three-dimensional residual stresses are calculated by an elastic FEM analysis from eigen-strains those can be evaluated quantitatively by an inverse analysis from released strains measured by strain gauges while the geometric boundary condition or material properties of the object has been changed. However, inelastic strains are newly created on the machined surface, the estimation accuracy of this method becomes relatively poor because the eigen-strains before and after measurements have to be the same. In this study, a calculation technique to evaluate not only initial eigen-strains but also processing strains is shown, and effectiveness of this method is demonstrated numerically in the bead flush method based on the eigen-strain method. Although estimation accuracy of processing strains was poorer, three-dimensional residual stresses for whole region could be evaluated accurately from measured strains without measurement errors.

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Kwon, Young W. "Failure Analysis of Composite Structures Using Multiscale Technique." Materials Science Forum 995 (June 2020): 209–13. http://dx.doi.org/10.4028/www.scientific.net/msf.995.209.

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Failure analyses of laminated fibrous composite structures were conducted using the failure criteria based on a multiscale approach. The failure criteria used the stresses and strains in the fiber and matrix materials, respectively, rather than those smeared values at the lamina level. The failure modes and their respective failure criteria consist of fiber failure, matrix failure and their interface failure explicitly. In order to determine the stresses and strains at the constituent material level (i.e. fiber and matrix materials), analytical expressions were derived using a unit-cell model. This model was used for the multiscale approach for both upscaling and downscaling processes. The failure criteria are applicable to both quasi-static loading as well as dynamic loading with strain rate effects.

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Wang, Chen, Jia He Li, and Zheng Wang. "Mechanical Analysis and Numerical Simulation of Steel-Ring and Rigid-Frame Restrained Concrete." Advanced Materials Research 535-537 (June 2012): 1745–50. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.1745.

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The complicated counterbalance system of steel ring and concrete-ring，rigid-frame and concrete-plate was analyzed and simplified under the restrain deformation and strains. The material parameters of early-age concrete are measured. Based on these work, the corresponding mechanical models were established and a special tool was employed for the meshing of model, and then, internal stress and strain induced by shrinkage of early-age concrete on restrained conditions were studied by FEM. The self-induced tensile stresses and strains in the restrain concrete can be calibrated，on the basis of which the elastic strains and tensile stresses would be calculated. So, the results of the numerical simulation reveal the law of the stress and strain distribution perfectly. It is significant to contrast the restraint characters of steel-ring and rigid-frame. The early-age shrinkage behaviors can be studied in depth.

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Frishter, Lyudmila. "Comparison of the stress and strain intensity factors for the corner area of the structure boundary." MATEC Web of Conferences 193 (2018): 03029. http://dx.doi.org/10.1051/matecconf/201819303029.

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The stress-strain state of structures in areas with corner cut-outs and cuts of boundaries features the occurrence of areas of stress concentration and requires assessment of strength and reliability of facilities, which is a relevant task in engineering practice. Theoretical analysis of stress-strain state (SSS) of corner cut-outs zones of the area boundary is reduced to the study of singular solutions of the elasticity theory problem with exponential features. At that, the concept of stress or strain concentration in an irregular point of the area boundary is meaningless. This paper considers the stress-strain state in the vicinity of the top of the corner cut-out of the flat area boundary, which is recorded using the intensity factors as limit values of stresses and strains. We give two approaches for obtaining the limit values for stress and strain in the vicinity of an irregular point of the plane area boundary using the stress intensity factors and the strain intensity factors. The stress-strain state in the corner cut-outs zone of structures and buildings boundary recorded in the form of limit values of stresses and strains may further be used to determine and record the influence of changing the factors of intensity of stresses and strains on SSS of structures, which is a separate task of solid mechanics. The difference in the expressions of stresses and displacements obtained for limit values of stresses and strains determines practical significance of the work when carrying out experiments and at determination of critical values of stresses and strains.

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Czinkota, Sid. "Structural analysis of pipeline stresses created by line lowering." Canadian Journal of Civil Engineering 14, no. 6 (December 1, 1987): 719–27. http://dx.doi.org/10.1139/l87-109.

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To increase the depth of soil which covers a buried steel pipeline, the line can be lowered without cutting and welding. The degree of curvature in the new profile is the critical factor for controlling the resultant strains. Presented are two methods of calculating the required profile for a line containing high-pressure natural gas. One of the two is selected as being more efficient than the other and is compared with other known methods. Finally, a case history using the new method is presented. Key words: pipelines, gas pipelines, structural analysis, stress analysis, axial stress, axial strain, deflection, curvature, profiles.

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Shih, C. F., R. J. Asaro, and N. P. O’Dowd. "Elastic-Plastic Analysis of Cracks on Bimaterial Interfaces: Part III—Large-Scale Yielding." Journal of Applied Mechanics 58, no. 2 (June 1, 1991): 450–63. http://dx.doi.org/10.1115/1.2897206.

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In Parts I and II, the structure of small-scale yielding fields of interface cracks were described in the context of small strain plasticity and J2 deformation theory. These fields are members of a family parameterized by the plastic phase angle ξ which also determines the shape or phase of the plastic zone. Through full-field analysis, we showed the resemblance between the plane-strain interface crack-tip fields and mixed-mode HRR fields in homogeneous material. This connection was exploited, to the extent possible, inasmuch as the interface fields do not appear to have a separable form. The present investigation is focused on “opening” dominated load states (| ξ | ≤ π/6) and the scope is broadened to include finite ligament plasticity and finite deformation effects on near-tip fields. We adopt a geometrically rigorous formulation of J2 flow theory taking full account of crack-tip blunting. Our results reveal several surprising effects, that have important implications for fracture, associated with finite ligament plasticity and finite strains. For one thing the fields that develop near bimaterial interfaces are more intense than those in homogeneous material when compared at the same value of J or remote load. For example, the plastic zones, plastic strains, and the crack-tip openings, δt, that evolve near bimaterial interfaces are considerably larger than those that develop in homogeneous materials. The stresses within the finite strain zone are also higher. In addition, a localized zone of high hydrostatic stresses develops near the crack tip but then expands rapidly within the weaker material as the plasticity spreads across the ligament. These stresses can be as much as 30 percent higher than those in homogeneous materials. Thus, the weaker material is subjected to large stresses as well as strains—states which promote ductile fracture processes. At the same time, the accompanying high interfacial stresses can promote interfacial fracture.

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Nilsson, R. N., I. Oost, and P. C. Hopman. "Viscoelastic Analysis of Full-Scale Pavements: Validation of VEROAD." Transportation Research Record: Journal of the Transportation Research Board 1539, no. 1 (January 1996): 81–87. http://dx.doi.org/10.1177/0361198196153900111.

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VEROAD, a linear viscoelastic multilayer computer program, takes the time dependence of road building materials into consideration. VEROAD calculates the responses (displacements, stresses, and strains) of a pavement structure subjected to a moving, sliding load. The validation of VEROAD (for longitudinal and transversal strain results) is described. The calculated strains were compared with measured strains from two full-scale pavement tests: the road track machine test in Denmark and the linear tracking apparatus test in the Netherlands. Measurements from these tests indicate distinct viscoelastic strain curves, that is, time retardation and asymmetry. The study indicates that VEROAD is able to calculate the pavement behavior (both longitudinal and transversal strains) as it was measured in these two full-scale tests. VEROAD-calculated strain curves have the same shape as the measured curves.

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Lee, Ken-ichi, Nigel P. French, Geoff Jones, Yukiko Hara-Kudo, Sunao Iyoda, Hideki Kobayashi, Yoshiko Sugita-Konishi, Hirokazu Tsubone, and Susumu Kumagai. "Variation in Stress Resistance Patterns amongstxGenotypes and Genetic Lineages of Shiga Toxin-Producing Escherichia coli O157." Applied and Environmental Microbiology 78, no. 9 (February 24, 2012): 3361–68. http://dx.doi.org/10.1128/aem.06646-11.

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ABSTRACTTo evaluate the relationship between bacterial genotypes and stress resistance patterns, we exposed 57 strains of Shiga toxin-producingEscherichia coli(STEC) O157 to acid, freeze-thaw, heat, osmotic, oxidative, and starvation stresses. Inactivation rates were calculated in each assay and subjected to univariate and multivariate analyses, including principal component analysis (PCA) and cluster analysis. Thestxgenotype was determined for each strain as was the lineage-specific polymorphism assay (LSPA6) genotype. In univariate analyses, strains of thestx1stx2genotype showed greater resistance to heat than strains of thestx1stx2cgenotype; moreover, strains of thestx1stx2genotype showed greater resistance to starvation than strains of thestx2orstx2cgenotypes. LSPA6 lineage I (LI) strains showed greater resistance to heat and starvation than LSPA6 lineage II (LII) strains. PCA revealed a general trend that a strain with greater resistance to one type of stress tended to have greater resistance to other types of stresses. In cluster analysis, STEC O157 strains were grouped into stress-resistant, stress-sensitive, and intermediate clusters. Instxgenotypes, all strains of thestx1stx2genotype were grouped with the stress-resistant cluster, whereas 72.7% (8/11) of strains of thestx1stx2cgenotype grouped with the stress-sensitive cluster. In LI strains, 77.8% (14/18) of the strains were grouped with the stress-resistant cluster, whereas 64.7% (11/17) of LII strains were grouped with the stress-sensitive cluster. These results indicate that the genotypes of STEC O157 that are frequently associated with human illness, i.e., LI or thestx1stx2genotype, have greater multiple stress resistance than do strains of other genotypes.

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Nam, Jeong-Hee, Seong-Min Kim, and Moon C. Won. "Measurement and Analysis of Early-Age Concrete Strains and Stresses." Transportation Research Record: Journal of the Transportation Research Board 1947, no. 1 (January 2006): 79–90. http://dx.doi.org/10.1177/0361198106194700108.

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Hatami, Ali, Samira Payan, and Mojtaba Hosseini. "Numerical analysis of thermal stresses and strains of annular finned tube bundle in turbulent flow regime." Mechanics & Industry 21, no. 6 (2020): 601. http://dx.doi.org/10.1051/meca/2020073.

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In this paper, the effect of turbulent flow on the thermal stresses and strains created in an annular finned-tube bundle is studied. The finite volume method and the transition SST model, along with the SIMPLE algorithm, are used to solve the flow equations, and the finite element method is used to solve the thermal stress equations in solid. The results obtained from the effective stress and strain in the annular fins bundle show that despite the temperature difference of less than 1 degree between the base and the edge of the fin, the amount of thermal stresses cannot be ignored and the asymmetric distribution of temperature in the fins leads to the shear stresses which play a key role in determining the maximum position of the effective stresses in some rows. The results show that the amount of effective stress and strain in the third and fourth rows are significantly smaller than the first and second rows. The results also show that the highest amount of the effective stress occurs in the first row and the fin base at zero-degree angle, the value of which is 0.6 MPa. The predominance of the tangential stresses at the fin base in this row is the cause of this issue. However, in the second fins onwards, although the tangential stresses are still higher, the greater asymmetry of the temperature around the fins in these rows leads to comparability of the shear stresses with tangential stresses and creates the maximum effective stress at angles other than zero degree. Therefore, according to the results of this paper, the analysis of the flow around the annular fins is necessary to calculate thermal stress and strains and it determines the vulnerable points in each tube row. It is natural that with increasing temperature difference between the base and the edge of the fin and with increasing fin hight, the importance of these studies increases.

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Lau, J., R. Subrahmanyan, D. Rice, S. Erasmus, and C. Li. "Fatigue Analysis of a Ceramic Pin Grid Array Soldered to an Orthotropic Epoxy Substrate." Journal of Electronic Packaging 113, no. 2 (June 1, 1991): 138–48. http://dx.doi.org/10.1115/1.2905379.

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Thermal stresses and strains in the solder joints and plated-through-hole (PTH) copper pads/barrels of a pin-grid array (PGA) assembly under thermal cycling conditions have been determined in the present study. There are two major systems of thermal stresses/strains acting at the solder joint and copper. One is the transverse shear and vertical normal stress/strain due to the local thermal expansion mismatch between the pin, solder, copper, and FR-4. The other is the horizontal normal stress/strain due to the global thermal expansion mismatch between the ceramic PGA and the FR-4 printed circuit board (PCB). The effects of the local thermal expansion mismatch on the reliability of solder joint and PTH copper have been determined using a 3-D orthotropic-elastoplastic finite element method. The effects of the global thermal expansion mismatch on the reliability of solder joint and PTH copper have been determined by fatigue experiments. Fatigue life of the solder joint and PTH copper was then estimated based on the calculated strains and the fatigue data on solders and coppers.

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Liu, Y., and N. J. Shen. "The residual stress and strain solutions of autofrettaged pressure vessels with a cone and cylinder connection." Journal of Strain Analysis for Engineering Design 27, no. 1 (January 1, 1992): 7–14. http://dx.doi.org/10.1243/03093247v271007.

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This paper presents analysis and experimental research on an autofrettaged pressure vessel with a cone and cylinder connection. Non-linear loading stresses and strains and the unloading residual stresses and strains are considered. The residual stress and strain fields are obtained by the non-linear axisymmetric boundary element method (BEM). The results of the BEM are verified by means of the finite element method (FEM) program ADINA and compared with autofrettaged high pressure experiments. It is concluded that the calculated residual strains are in reasonable agreement with those determined experimentally.

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Pintilie, Alexandru, Melat Bormambet, and Viorel Bogdan Rădoiu. "Stresses and Strains in Main Gas Pipelines due to Ramifications." Advanced Materials Research 1111 (July 2015): 163–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1111.163.

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In this paper is presented a study of stresses and strains due ramification to consumers of main gas pipeline. It's numerically analyzed the influence of main pipe's ramification due to modification of mechanical and geometrical parameters. Modeled loads are based on evaluation of internal forces of thin shell and induced loads by circular weld thermal field. The study of stresses and strain it's made using finite elements method by a static tri dimensional analysis performed both for evaluation of stresses and strains in presence and absence of internal pressure. The obtained results represent a comparative factor for technical regulation in the safety assessment in operation of natural gas pipelines.

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Jiang, Yanyao, Biqiang Xu, and Huseyin Sehitoglu. "Three-Dimensional Elastic-Plastic Stress Analysis of Rolling Contact." Journal of Tribology 124, no. 4 (September 24, 2002): 699–708. http://dx.doi.org/10.1115/1.1491978.

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Three-dimensional elastic-plastic rolling contact stress analysis was conducted incorporating elastic and plastic shakedown concepts. The Hertzian distribution was assumed for the normal surface contact load over a circular contact area. The tangential forces in both the rolling and lateral directions were considered and were assumed to be proportional to the Hertzian pressure. The elastic and plastic shakedown limits obtained for the three-dimensional contact problem revealed the role of both longitudinal and lateral shear traction on the shakedown results. An advanced cyclic plasticity model was implemented into a finite element code via the material subroutine. Finite element simulations were conducted to study the influences of the tangential surface forces in the two shear directions on residual stresses and residual strains. For all the cases simulated, the p0/k ratio (p0 is the maximum Hertzian pressure and k is the yield stress in shear) was 6.0. The Qx/P ratio, where Qx is the total tangential force on the contact surface in the rolling direction and P is the total normal surface pressure, ranged from 0 to 0.6. The Qy/P ratio (Qy is the total tangential force in the lateral direction) was either zero or 0.25. Residual stresses increase with increasing rolling passes but tend to stabilize. Residual strains also increase but the increase in residual strain per rolling pass (ratchetting rate) decays with rolling cycles. Residual stress levels can be as high as 2k when the Qx/P ratio is 0.6. Local accumulated shear strains can exceed 20 times the yield strain in shear after six rolling passes under extreme conditions. Comparisons of the two-dimensional and three-dimensional rolling contact results were provided to elucidate the differences in residual stresses and ratchetting strain predictions.

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D. D’Lima, Darryl, Peter C. Chen, and Clifford W. Colwell Jr. "Osteochondral Grafting: Effect of Graft Alignment, Material Properties, and Articular Geometry." Open Orthopaedics Journal 3, no. 1 (August 6, 2009): 61–68. http://dx.doi.org/10.2174/1874325000903010061.

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Osteochondral grafting for cartilage lesions is an attractive surgical procedure; however, the clinical results have not always been successful. Surgical recommendations differ with respect to donor site and graft placement technique. No clear biomechanical analysis of these surgical options has been reported. We hypothesized that differences in graft placement, graft biomechanical properties, and graft topography affect cartilage stresses and strains. A finite element model of articular cartilage and meniscus in a normal knee was constructed. The model was used to analyze the magnitude and the distribution of contact stresses, von Mises stresses, and compressive strains in the intact knee, after creation of an 8-mm diameter osteochondral defect, and after osteochondral grafting of the defect. The effects of graft placement, articular surface topography, and biomechanical properties were evaluated. The osteochondral defect generated minimal changes in peak contact stress (3.6 MPa) relative to the intact condition (3.4 MPa) but significantly increased peak von Mises stress (by 110%) and peak compressive strain (by 63%). A perfectly matched graft restored stresses and strains to near intact conditions. Leaving the graft proud by 0.5 mm generated the greatest increase in local stresses (peak contact stresses = 6.7 MPa). Reducing graft stiffness and curvature of articular surface had lesser effects on local stresses. Graft alignment, graft biomechanical properties, and graft topography all affected cartilage stresses and strains. Contact stresses, von Mises stresses, and compressive strains are biomechanical markers for potential tissue damage and cell death. Leaving the graft proud tends to jeopardize the graft by increasing the stresses and strains on the graft. From a biomechanical perspective, the ideal surgical procedure is a perfectly aligned graft with reasonably matched articular cartilage surface from a lower load-bearing region of the knee.

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Liu, Cui Rong, Hui Qin Chen, Juan Li, and Qing Sen Meng. "Anodic Bonding Mechanism of Pyrex Glass and Kovar Alloy and its Residual Stress Analysis." Advanced Materials Research 922 (May 2014): 435–40. http://dx.doi.org/10.4028/www.scientific.net/amr.922.435.

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Anodic bonding experiments of Pyrex glass and Kovar alloy have been carried out in this investigation. By means of SEM and EDS, microstructures and chemical elements in the joining interfaces were analyzed. With XRD, phase structures in the interfaces were also analyzed. The results show that the joint is made up of three different layers, which are Kovar alloy layer, transition layer and Pyrex glass layer. The transition layer are spinal oxides, which are FeO·SiO2. By means of MARC software, residual stresses and strains were investigated for the anodic bonding samples of Pyrex glass/Kovar alloy. The maximum residual stress located in the transition layer and the maximum strain located in the Kovar alloy layer. Residual stresses and strains of the sample are significant small and uniform.

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Szefer, G., and D. Jasińska. "Modeling of strains and stresses of material nanostructures." Bulletin of the Polish Academy of Sciences: Technical Sciences 57, no. 1 (March 1, 2009): 41–46. http://dx.doi.org/10.2478/v10175-010-0103-6.

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Modeling of strains and stresses of material nanostructuresStress and deformation analysis of materials and devices at the nanoscale level are topics of intense research in materials science and mechanics. In these investigations two approaches are observed. First, natural for the atomistic scale description is based on quantum and molecular mechanics. Second, characteristic for the macroscale continuum model description, is modified by constitutive laws taking atomic interactions into account. In the present paper both approaches are presented. For a discrete system of material points (atoms, molecules, clusters), measures of strain and stress, important from the mechanical viewpoint, are given. Numerical examples of crack propagation and deformation of graphite sheets (graphens) illustrate the behavior of the discrete systems.

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Sharpe, William N. "ASME 1993 Nadai Lecture—Elastoplastic Stress and Strain Concentrations." Journal of Engineering Materials and Technology 117, no. 1 (January 1, 1995): 1–7. http://dx.doi.org/10.1115/1.2804366.

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Elastic stress concentration factors are familiar and easily incorporated into the design of components or structures through charts or finite element analysis. However when the material at the most concentrated location no longer behaves elastically, computation of the local stresses and strains is not so easy. Local elastoplastic behavior is an especially important consideration when the loading is cyclic. This paper summarizes the predictive capability of the Neuber and the Glinka models that relate gross loading to the local stresses and strains. The author and his students have used a unique laser-based technique capable of measuring biaxial strains over very short gage lengths to evaluate the two models. Their results, as well as those from earlier studies by other researchers using foil gages, lead to the general conclusion that the Neuber model works best when the local region is in a state of plane stress and the Glinka model is best for plane strain. There are intermediate levels of constraint that are neither plane stress nor plane strain. This paper presents a recommended practice for predicting the local elastoplastic stresses and strains for any constraint. First, one computes or estimates the initial elastic strains. Then, based on the amount of elastic constraint, one selects the appropriate model to compute the local elastoplastic stresses and strains.

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Ezendiokwere, Nnamdi E., Victor J. Aimikhe, Adewale Dosunmu, and Ogbonna F. Joel. "Influence of depth on induced geo-mechanical, chemical, and thermal poromechanical effects." Journal of Petroleum Exploration and Production Technology 11, no. 7 (May 14, 2021): 2917–30. http://dx.doi.org/10.1007/s13202-021-01174-6.

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AbstractDelivering efficient and cost-effective drilled and excavated holes require effective prediction of instability along the hole profile. Most drilled and excavated hole stability analyses in the literature are performed for a given zone without considering the influence of depth. This study focused on determining the influence of depth on induced geo-mechanical, chemical, and thermal stresses and strains in drilled or excavated holes. To this end, a new porochemothermoelastic model was developed based on extended poroelastic theory, and the developed model was employed in determining induced strains and stresses for an oil and gas well case study, using data from the literature. The study delineated the different significance levels of geo-thermal-, chemical-, and thermal-induced strains and stresses as depth increased. From the results obtained, it was clear that at shallow depths, chemically induced strains and stress were the most significant formation perturbations responsible for instability of drilled and excavated holes. On the other hand, at deeper depths, geo-mechanical-induced strains and stress were the most predominant. Comparatively, thermally induced strains and stresses were found to be the least significant formation perturbations responsible for instability of drilled and excavated holes. For this case study, the results indicated that chemical strains and stresses were more prominent at depths below 170 m, accounting for more than 50% of the total stresses and strains. At 170 m, both chemical and geo-mechanical stress and strain had equal contributions to the overall stress and strain. However, as depth increased, the percentage contribution of the geo-mechanical component increased and accounted for about 80% of the total strains and stresses at 1000 m, which increased to 98.48% at depths of 6000 m and beyond. The findings of this study will provide guide for future studies on the application of extended poroelasticity theory in solving instability problems of drilled and excavated holes.

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Wen, Z. F., and X. S. Jin. "Elastic-Plastic Finite-Element Analysis of Repeated, Two-Dimensional Wheel-Rail Rolling Contact under Time-Dependent Load." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 220, no. 5 (May 1, 2006): 603–13. http://dx.doi.org/10.1243/09544062jmes201.

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A study was performed using a finite-element model to obtain stresses, strains, and deformations for repeated, two-dimensional rolling contact of a locomotive driving wheel and a rail under time-dependent load. An advanced cyclic plasticity model was used with a commercial finite element code via a material subroutine. The time-dependent load was considered a harmonic variation of the wheel-rail normal contact force. The normal contact pressure was assumed to follow the Hertzian distribution and the tangential force followed the Carter distribution. A wavy profile is formed on the running surface of the rail subjected to the harmonic variation of the normal (vertical) contact force. The developed wavelength of the profile corresponds to the frequency of the normal contact force for the actual train speed. The creepage or rolling-sliding condition plays an important role in the residual strains and deformations, but its influence on the residual stresses is insignificant. The residual stresses at the surface decrease with increasing rolling passes and gradually tend to stabilize. The residual strains and surface displacements increase with increasing rolling cycle, but the increases in residual strain and surface displacement per rolling pass (ratchetting rate) decay. The residual stresses, strains, and deformations near the wave trough of the residual wavy deformation are larger than those near the wave crest. For any given creepage including zero value, when the number of rolling passes increases, the surface depth of the wavy-deformed surface increases but the ratchetting rate decays. The results are useful in investigating the influence of plastic deformation on rail corrugation.

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Wen, Zefeng, Xuesong Jin, and Yanyao Jiang. "Elastic-Plastic Finite Element Analysis of Nonsteady State Partial Slip Wheel-Rail Rolling Contact." Journal of Tribology 127, no. 4 (June 21, 2005): 713–21. http://dx.doi.org/10.1115/1.2033898.

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A finite element analysis with the implementation of an advanced cyclic plasticity theory was conducted to study the elastic-plastic deformation under the nonsteady state rolling contact between a wheel and a rail. The consideration of nonsteady state rolling contact was restricted to a harmonic variation of the wheel-rail normal contact force. The normal contact pressure was idealized as the Hertzian distribution, and the tangential force presented by Carter was used. Detailed rolling contact stresses and strains were obtained for repeated rolling contact. The harmonic variation of the normal (vertical) contact force results in a wavy rolling contact surface profile. The results can help understand the influence of plastic deformation on the rail corrugation initiation and growth. The creepage or stick-slip condition greatly influences the residual stresses and strains. While the residual strains and surface displacements increased at a reduced rate with increasing rolling passes, the residual stresses stabilize after a limited number of rolling passes. The residual stresses and strains near the wave trough of the residual wavy deformation are higher than those near the wave crest.

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Mrozinski, Stanislaw. "True and Nominal Stress during Low Cycle Fatigue Tests of Metals." Solid State Phenomena 250 (April 2016): 139–44. http://dx.doi.org/10.4028/www.scientific.net/ssp.250.139.

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In this paper results of P91 cast steel after static and fatigue tests were presented. During the tests longitudinal and transverse strains of the specimen were measured. Basing on the results a comparative analysis of nominal stresses σn,true stresses σrz, nominal strain energy ΔWpl (n) and true strain energy ΔWpl (n) was carried out. It was stated that differences between determined paramters rise with increasing strain.

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Badr, E. A., J. R. Sorem, and S. M. Tipton. "Residual Stress Estimation in Crossbores With Bauschinger Effect Inclusion Using FEM and Strain Energy Density." Journal of Pressure Vessel Technology 121, no. 4 (November 1, 1999): 358–63. http://dx.doi.org/10.1115/1.2883715.

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Crossbore intersections in liquid ends of positive displacement pumps (PDPs) have regions with high stress concentration. Due to the cyclic loading that occurs in most PDPs, these stress concentration points are susceptible to fatigue cracking. In order to prolong their life, the liquid ends are often overpressurized (autofrettaged), thus inducing beneficial compressive hoop stresses in these critical regions upon removal of the autofrettage pressure. This autofrettage process drives the region of high stress concentration beyond the elastic limit and well into the elastic-plastic region. Elastic-plastic stresses and strains due to loading and unloading were analyzed in crossbore geometries, with Bauschinger effect included, using 3-D finite element analysis of the liquid end. For comparison, an analytical approach was developed, based on the strain energy density criterion first proposed by Glinka. The approach was modified to include the Bauschinger effect for precise estimation of such stresses and strains. Good correlation was observed between elastic-plastic crossbore stresses and strains predicted by the analytical approach and the finite element analysis.

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Smith Neto, P., E. S. Palma, and V. M. Figueiredo Bicalho. "Stress Analysis in Automobile Components Using Reflexive Photoelasticity Technique." Applied Mechanics and Materials 5-6 (October 2006): 117–24. http://dx.doi.org/10.4028/www.scientific.net/amm.5-6.117.

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The main objective of this work was to introduce Reflexive Photoelasticity Technique in qualifying automotive components at Fiat Automoveis S.A in Brazil. Actual stresses were determined in a simple geometry plate and also in nodes of a body shell of a passenger vehicle by using reflexive photoelasticity methodology. Initially, tests were performed in welded steel plates submitted to traction loads. These plates were previously coated with birrefringent plastic material. External loads were applied through hydraulic MTS actuators. Stress and strain distribution in welded points neighboring areas using reflexive polariscope were quantitative determined. Simultaneously, these stress and strains acting on the welded plate were determined using strain gauges. The results from both experimental techniques (photoelasticity and strain gauges) were compared with those obtained from a numerical model using finite element method. The results were correlated and analyzed. Finally, reflexive photoelasticity technique was used to determine the stresses in nodes of a body shell of a passenger vehicle. Through this analysis it was possible to determine critical points in the structure with peak stresses.

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Loov, Robert. "Modifications to the interpretation of the stresses and strains determined using constant strain triangular elements." International Journal for Numerical Methods in Engineering 22, no. 1 (January 1986): 249–66. http://dx.doi.org/10.1002/nme.1620220119.

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Yuan, Yuan, Kun Shi, and Kai Liu. "An Approximate Algorithm for Shakedown on Gear Contact." Applied Mechanics and Materials 160 (March 2012): 59–63. http://dx.doi.org/10.4028/www.scientific.net/amm.160.59.

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A model of gear contact has been established based on Hertz theory. Local coordinates are constructed on different meshing points because curvature of gear profile is not constant and then distributions of residual stresses and strains are given. Upper and lower bounds for the shakedown limits have been obtained. An approximate algorithm based on a stress invariant hypothesis and a stress/strain relaxation procedure is developed to solve residual stresses and strains accumulation in elastic-plastic stress analysis of gear contact. The steady-state residual stresses of gear under repeat meshing are calculated. The results are useful information for the strength design of gear.

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Huč, Sabina, Staffan Svensson, and Tomaž Hozjan. "Numerical analysis of moisture-induced strains and stresses in glued-laminated timber." Holzforschung 74, no. 5 (May 26, 2020): 445–57. http://dx.doi.org/10.1515/hf-2019-0025.

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AbstractChanges in relative humidity of the ambient air, RH (%), cause wetting and drying of wood material, which results in non-uniform moisture contents or moisture gradients, and consequently in moisture-induced stresses and strains in the glued-laminated timber (glulam) members. The aim of the present paper is to perform a hygro-mechanical analysis to predict the mechanical behavior of glulam specimens exposed to two RH regimes, causing wetting from 50% to 90% RH and drying from 90% to 50% RH, and compare the numerical to the experimental results. The aims are also to quantitatively analyze the influence of characteristic material parameters required in the multi-Fickian moisture transport model and the mechanical model on moisture-induced strains and stresses in glulam specimens and to determine the possibility of cracking of the material by analyzing the maximum tensile stresses perpendicular to the grain. Accurate numerical predictions of moisture contents and moisture-induced strains are obtained in the glulam specimens during wetting and drying as compared to the experimental results. The influence of a particular characteristic material parameter on moisture-induced strains and stresses is characterized as significant, but not crucial when a rough numerical estimation of the mechanical behavior of the glulam beam exposed to RH changes is required.

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Xu, Biqiang, and Yanyao Jiang. "Elastic-Plastic Finite Element Analysis of Partial Slip Rolling Contact." Journal of Tribology 124, no. 1 (March 26, 2001): 20–26. http://dx.doi.org/10.1115/1.1395630.

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The finite element model with the implementation of a robust cyclic plasticity theory was used to simulate the elastic-plastic stresses for the partial slip (stick-slip) line rolling contact. Detailed rolling contact stresses and strains were obtained for up to 40 rolling passes. The partial slip condition greatly affects the residual stress in the rolling direction and the residual shear strain within a thin layer of material near the contact surface. The residual stress in the axial direction was not significantly influenced by the partial slip condition. An increase in friction coefficient drives the location of maximum shear strain to the contact surface. In addition, a comparison was made between the finite element results and the results obtained from an approximate method.

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Kukuryk, Marcin. "Numerical analysis of strains and stresses in the hot cogging process." Journal of Applied Mathematics and Computational Mechanics 17, no. 3 (September 2018): 45–52. http://dx.doi.org/10.17512/jamcm.2018.3.04.

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Nuñez, J. E., and G. Glinka. "Analysis of non-localized creep induced strains and stresses in notches." Engineering Fracture Mechanics 71, no. 12 (August 2004): 1791–803. http://dx.doi.org/10.1016/s0013-7944(03)00208-x.

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Renji, K., and S. Josephine Kelvina Florence. "Estimation of strains / stresses in composite panels using statistical energy analysis." Journal of Sound and Vibration 408 (November 2017): 400–410. http://dx.doi.org/10.1016/j.jsv.2017.07.042.

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Anisimov, A. G., B. Müller, J. Sinke, and R. M. Groves. "Analysis of thermal strains and stresses in heated fibre metal laminates." Strain 54, no. 2 (January 9, 2018): e12260. http://dx.doi.org/10.1111/str.12260.

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CHAUDHRY, H. R., B. BUKIET, T. FINDLEY, and A. B. RITTER. "STRESSES AND STRAINS IN THE PASSIVE LEFT VENTRICLE." Journal of Biological Systems 04, no. 04 (December 1996): 535–54. http://dx.doi.org/10.1142/s021833909600034x.

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In this paper, we estimate the stresses and strains from the equatorial region down to the apex of the heart by modeling the passive left ventricle as a frustrum of a thick hollow cone. Large deformation theory has been employed in this analysis. Furthermore, the effects of residual stresses and the anisotropy due to muscle fiber orientation have been included. It is observed that circumferential stress, which is the most important physiologically, decreases considerably at the endocardium and is more evenly distributed through the wall when residual stresses are taken into account. The stresses also decrease as we go from the equatorial region to the apex. Because heart muscles physically have residual stresses, the consequent lower stress gradient through the wall enhances the diastolic function of the left ventricle.

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Chen, Junfu, Zhiping Guan, Pinkui Ma, Zhigang Li, and Xiangrui Meng. "The improvement of stress correction in post-necking tension of cylindrical specimen." Journal of Strain Analysis for Engineering Design 54, no. 3 (April 2019): 209–22. http://dx.doi.org/10.1177/0309324719852875.

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In post-necking tension of cylindrical specimen, the stress corrections based on the current analytical models have relatively significant errors at large strains. In this study, the prediction capability of these models involving Bridgman model, Siebel model and Chen model is evaluated by performing a series of finite element simulations of uniaxial tension of cylindrical specimen with different hardening exponents varied from 0.05 to 0.3. Numerical analysis of stress and strain distributions on the necking cross section indicates that the considerable errors of the corrected stresses corresponding to large strains might be mainly attributed to the assumption of uniform strain distribution on the necking cross section in these analytical models. The modification strategies of these models are presented in order to improve their prediction accuracy of post-necking stresses, taking geometrical configuration of neck and material properties into consideration. Accordingly, the modification formulas are proposed based on simulation results, involving the radius of cross section of neck and the hardening exponent. Finally, these formulas are used to correct the stresses in the post-necking tension of Q345 cylindrical specimen, which are compared with the stresses identified through inverse method. The results indicate that the modified models significantly improve the prediction accuracy of post-necking stresses at large strains.

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Yuan, M. G., and Y. Ueda. "Prediction of Residual Stresses in Welded T- and I-Joints Using Inherent Strains." Journal of Engineering Materials and Technology 118, no. 2 (April 1, 1996): 229–34. http://dx.doi.org/10.1115/1.2804892.

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In order to develop a predicting method of residual stresses in fillet welded T- and I-joints, a concept of inherent strain, being regarded as a source of the residual stresses, was introduced. With the proposed method, the residual stress of an interested weldment may be predicted by performing an elastic analysis, in which the inherent strain is replaced to equivalent distributed loads. The inherent strain distributions in various welded T- and I-joints were investigated by numerical simulations. The results showed that the inherent strains distributing in flange side and in web side of the several joints are almost the same. The inherent strains vary not only with the average temperature rise due to welding, but with the geometric ratio of the joints. Being simplified by a trapezoid curve, the inherent strain distribution in a fillet weld was expressed by formulas, in which heat input, material properties, and geometric dimensions were taken into account. Welding residual stresses in T- and I-joints, predicted by the proposed method employing the derived formulas, were compared with those obtained by thermal elasto-plastic analysis, and good agreement was recognized. The validity of the proposed method was also confirmed by experiments.

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Kik, Tomasz, Marek Slovacek, Jaromir Moravec, and Mojmir Vanek. "Numerical Analysis of Residual Stresses and Distortions in Aluminium Alloy Welded Joints." Applied Mechanics and Materials 809-810 (November 2015): 443–48. http://dx.doi.org/10.4028/www.scientific.net/amm.809-810.443.

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Simulation software based on a finite element method have significantly changed the possibilities of determining welding strains and stresses at early stages of product design and welding technology development. But the numerical simulation of welding processes is one of the more complicated issues in analyses carried out using the Finite Element Method. A welding process thermal cycle directly affects the thermal and mechanical behaviour of a structure during the process. High temperature and subsequent cooling of welded elements generate undesirable strains and stresses in the structure. Knowledge about the material behaviour subjected to the welding thermal cycle is most important to understand process phenomena and proper steering of the process. The study presented involved the SYSWELD software-based analysis of MIG welded butt joints made of 1.0 mm thickness, 5xxx series aluminium alloy sheets. The analysis of strains and the distribution of stresses were carried out for several different cases of fixing and releasing of welded elements.

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Journal articles on the topic 'Strains and stresses – Analysis'

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