An empirical formulation for predicting welding-induced biaxial compressive residual stresses on steel stiffened plate structures and its application to thermal plate buckling prevention

Plated structures such as ships and offshore structures are constructed using welding techniques that attach support members (or stiffeners) to the plating. During this process, initial imperfections develop in the form of initial deformations (deflections or distortions) and residual stresses. These initial imperfections significantly affect the buckling and ultimate strength of these structures. Therefore, to assess the strength of welded plate structures, it is very important to predict the magnitude and pattern of welding-induced initial imperfections and their effects on buckling and ultimate strength. To determine the reliability of the prediction methods, it is desirable to validate the theoretical or numerical predictions of welding-induced initial imperfections through comparison with full-scale actual measurements. However, full-scale measurement databases are lacking, as they are costly to obtain. This study contributes to the development of a full-scale measurement database of welding-induced initial imperfections in steel-stiffened plate structures. The target structures are parts of real (full-scale) deckhouses in very large crude oil carrier class floating, production, storage and offloading unit structures. For parametric study purposes, four test structures by varying plate thickness are measured while the stiffener types and weld bead length are fixed. Modern technologies for measuring initial deformations and residual stresses are applied. The details of the measurement methods are documented for the use of other researchers and practicing engineers who want to validate their computational models for predicting welding-induced initial imperfections.

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Three-Dimensional Thermo-Elastic-Plastic Finite Element Method Modeling for Predicting Weld-Induced Residual Stresses and Distortions in Steel Stiffened-Plate Structures

World Journal of Engineering and Technology ◽

10.4236/wjet.2018.61010 ◽

2018 ◽

Vol 06 (01) ◽

pp. 176-200 ◽

Cited By ~ 5

Author(s):

Myung Su Yi ◽

Chung Min Hyun ◽

Jeom Kee Paik

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Residual Stresses ◽

Three Dimensional ◽

Stiffened Plate ◽

Plate Structures ◽

Elastic Plastic ◽

Finite Element Method Modeling ◽

Element Method

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FULL-SCALE MEASUREMENTS OF WELDING-INDUCED INITIAL DEFLECTIONS AND RESIDUAL STRESSES IN STEEL-STIFFENED PLATE STRUCTURES

The International Journal of Maritime Engineering ◽

10.5750/ijme.v160ia4.1074 ◽

2021 ◽

Vol 160 (A4) ◽

Author(s):

M S Yi ◽

C M Hyun ◽

J K Paik

Keyword(s):

Residual Stresses ◽

Ultimate Strength ◽

Plate Thickness ◽

Offshore Structures ◽

Full Scale ◽

Stiffened Plate ◽

Plate Structures ◽

Initial Imperfections ◽

Numerical Predictions ◽

Modern Technologies

Plated structures such as ships and offshore structures are constructed using welding techniques that attach support members (or stiffeners) to the plating. During this process, initial imperfections develop in the form of initial deformations (deflections or distortions) and residual stresses. These initial imperfections significantly affect the buckling and ultimate strength of these structures. Therefore, to assess the strength of welded plate structures, it is very important to predict the magnitude and pattern of welding-induced initial imperfections and their effects on buckling and ultimate strength. To determine the reliability of the prediction methods, it is desirable to validate the theoretical or numerical predictions of welding-induced initial imperfections through comparison with full-scale actual measurements. However, full-scale measurement databases are lacking, as they are costly to obtain. This study contributes to the development of a full-scale measurement database of welding-induced initial imperfections in steel-stiffened plate structures. The target structures are parts of real (full-scale) deckhouses in very large crude oil carrier class floating, production, storage and offloading unit structures. For parametric study purposes, four test structures by varying plate thickness are measured while the stiffener types and weld bead length are fixed. Modern technologies for measuring initial deformations and residual stresses are applied. The details of the measurement methods are documented for the use of other researchers and practicing engineers who welding-induced initial imperfections.

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A Review on Practical Use of Simple Analysis Method based on SDOF Model for the Stiffened Plate Structures subjected to Blast Loads

Journal of the Society of Naval Architects of Korea ◽

10.3744/snak.2020.57.2.070 ◽

2020 ◽

Vol 57 (2) ◽

pp. 70-79

Author(s):

Ul-Nyeon Kim ◽

Simsik Ha

Keyword(s):

Stiffened Plate ◽

Analysis Method ◽

Blast Loads ◽

Simple Analysis ◽

Plate Structures

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X-ray Determination of Compressive Residual Stresses in Spring Steel Generated by High-Speed Water Quenching

Materials ◽

10.3390/ma12071154 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1154

Author(s):

Diego E. Lozano ◽

George E. Totten ◽

Yaneth Bedolla-Gil ◽

Martha Guerrero-Mata ◽

Marcel Carpio ◽

...

Keyword(s):

Heat Treatment ◽

Residual Stresses ◽

High Speed ◽

Spring Steel ◽

X Ray Diffraction ◽

Laboratory Equipment ◽

X Ray ◽

Water Chamber ◽

Hardened Case ◽

Compressive Residual Stresses

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core microstructure. A special laboratory equipment was designed and built, which uses water as the quenching media in a high-speed water chamber. The severity of the cooling was characterized with embedded thermocouples to obtain the cooling curves at different depths from the surface. Samples were cooled for various times to produce different hardened case depths. The microstructure of specimens was observed with a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to estimate the magnitude of residual stresses on the surface of the specimens. Compressive residual stresses at the surface and sub-surface of about −700 MPa were obtained.

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Thermal Effects on Surface and Subsurface Modifications in Laser-Combined Deep Rolling

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp5020055 ◽

2021 ◽

Vol 5 (2) ◽

pp. 55

Author(s):

Robert Zmich ◽

Daniel Meyer

Keyword(s):

Surface Layer ◽

Residual Stresses ◽

Thermal Loads ◽

Deep Rolling ◽

Mechanical Loads ◽

Thermomechanical Process ◽

Compressive Stresses ◽

New Process ◽

Negative Effect ◽

Compressive Residual Stresses

Knowledge of the relationships between thermomechanical process loads and the resulting modifications in the surface layer enables targeted adjustments of the required surface integrity independent of the manufacturing process. In various processes with thermomechanical impact, thermal and mechanical loads act simultaneously and affect each other. Thus, the effects on the modifications are interdependent. To gain a better understanding of the interactions of the two loads, it is necessary to vary thermal and mechanical loads independently. A new process of laser-combined deep rolling can fulfil exactly this requirement. The presented findings demonstrate that thermal loads can support the generation of residual compressive stresses to a certain extent. If the thermal loads are increased further, this has a negative effect on the surface layer and the residual stresses are shifted in the direction of tension. The results show the optimum range of thermal loads to further increase the compressive residual stresses in the surface layer and allow to gain a better understanding of the interactions between thermal and mechanical loads.

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Additive Manufactured 316L Stainless-Steel Samples: Microstructure, Residual Stress and Corrosion Characteristics after Post-Processing

Metals ◽

10.3390/met11020182 ◽

2021 ◽

Vol 11 (2) ◽

pp. 182

Author(s):

Suvi Santa-aho ◽

Mika Kiviluoma ◽

Tuomas Jokiaho ◽

Tejas Gundgire ◽

Mari Honkanen ◽

...

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Sample Surface ◽

Post Processing ◽

Magnesium Chloride Solution ◽

Manufacturing Method ◽

Four Point Bending ◽

Traditional Manufacturing ◽

Processing Steps ◽

Compressive Residual Stresses

Additive manufacturing (AM) is a relatively new manufacturing method that can produce complex geometries and optimized shapes with less process steps. In addition to distinct microstructural features, residual stresses and their formation are also inherent to AM components. AM components require several post-processing steps before they are ready for use. To change the traditional manufacturing method to AM, comprehensive characterization is needed to verify the suitability of AM components. On very demanding corrosion atmospheres, the question is does AM lower or eliminate the risk of stress corrosion cracking (SCC) compared to welded 316L components? This work concentrates on post-processing and its influence on the microstructure and surface and subsurface residual stresses. The shot peening (SP) post-processing levelled out the residual stress differences, producing compressive residual stresses of more than −400 MPa in the AM samples and the effect exceeded an over 100 µm layer below the surface. Post-processing caused grain refinement and low-angle boundary formation on the sample surface layer and silicon carbide (SiC) residue adhesion, which should be taken into account when using the components. Immersion tests with four-point-bending in the heated 80 °C magnesium chloride solution for SCC showed no difference between AM and reference samples even after a 674 h immersion.

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Ultrasonic Evaluation of Compressive Residual Stress of Surface Treated Metals

Materials Science Forum ◽

10.4028/www.scientific.net/msf.490-491.184 ◽

2005 ◽

Vol 490-491 ◽

pp. 184-189 ◽

Cited By ~ 2

Author(s):

Farid Belahcene ◽

Xiaolai Zhou ◽

Jian Lu

Keyword(s):

Experimental Data ◽

Residual Stresses ◽

Nondestructive Evaluation ◽

Subsurface Layer ◽

Surface Mechanical Attrition Treatment ◽

Shallow Subsurface ◽

Ultrasonic Evaluation ◽

Mechanical Attrition ◽

Machine Parts ◽

Compressive Residual Stresses

Shot peening is an effective method of improving fatigue performance of machine parts in the industry by producing a thin surface layer of compressive residual stresses that prevents crack initiation and retards crack growth during service. Nondestructive evaluation of the prevailing compressive residual stresses in the shallow subsurface layer is realized by the critically refracted longitudinal (Lcr) waves. This paper presents experimental data obtained on SMAT (surface mechanical attrition treatment) steel alloy S355 sample. Comparative travel-time shows that there are statistically significant differences in treated and untreated specimen. With knowledge of the acoustoelastic constants which are obtained by a test calibration, the experimental data indicates that compressive residual stresses are distributed near subsurface (hundreds of micron). These stress results show that the Lcr technique is efficient for evaluation of residual stresses after the surface treatment.

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The Residual Stresses Generated by Deep Rolling and their Stability in Fatigue & Application to Deep-Rolled Crankshafts

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.45 ◽

2006 ◽

Vol 524-525 ◽

pp. 45-50 ◽

Cited By ~ 9

Author(s):

H. Michaud ◽

Jean Michel Sprauel ◽

F. Galzy

Keyword(s):

Residual Stresses ◽

Fatigue Resistance ◽

Experimental Validation ◽

Crack Arrest ◽

Cyclic Fatigue ◽

Rolling Process ◽

Fatigue Behaviour ◽

Deep Rolling ◽

Bending Fatigue ◽

Compressive Residual Stresses

In this work, the effect of steel grade on the fatigue resistance of deep-rolled crankshafts is analysed. In the first part of this paper, the mechanisms leading to the increase of the fatigue resistance brought by the deep rolling treatment, is presented. This reinforcement is mainly linked to crack arrest due both to a decrease of the in-depth stress concentration factor and to remaining compressive residual stresses induced by the deep rolling. In a second part, an analytical model of residual stresses generation by deep-rolling and fatigue is presented. In this model the low cyclic fatigue behaviour of the steel is taken into account, and the residual stress stability with bending fatigue cycling can be predicted. After a presentation of the experimental validation on two different microstructures (baintic and ferrito- perlitic), this model is used for analysing the main parameters of the deep-rolling process and fatigue resistance.

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