Engineering › Mechanical Engineering

Welding Techniques and Residual Stresses

Works Count: 75972

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Description

This cluster of papers focuses on various welding techniques, including laser welding, gas tungsten arc welding, and electron beam welding. It explores topics such as residual stress measurement, numerical simulation of welding processes, heat transfer and fluid flow during welding, and the effects of welding parameters on microstructure and mechanical properties. Additionally, the cluster delves into the optimization of welding processes and the impact of residual stresses on fatigue performance.

Keywords

Welding; Residual Stress; Laser Welding; Numerical Simulation; Heat Transfer; Weld Pool Dynamics; Keyhole Formation; Process Optimization; Microstructure Analysis; Fatigue Performance

Hole-drilling strain-gage method of measuring residual stresses

1966-12-01

Norbert J. Rendler , Irwin Vigness

Welding metallurgy and weldability of stainless steels

2005-12-01

John C. Lippold , D. J. Kotecki

Preface. 1. Introduction. 2. Phase Diagrams. 3. Alloying Elements and Constitution Diagrams. 4. Martensitic Stainless Steels. 5. Ferritic Stainless Steels. 6. Austenitic Stainless Steels. 7. Duplex Stainless Steels. 8. Precipitation-Hardening … Preface. 1. Introduction. 2. Phase Diagrams. 3. Alloying Elements and Constitution Diagrams. 4. Martensitic Stainless Steels. 5. Ferritic Stainless Steels. 6. Austenitic Stainless Steels. 7. Duplex Stainless Steels. 8. Precipitation-Hardening Stainless Steels. 9. Dissimilar Welding of Stainless Steels. 10. Weldability Testing. Appendix 1: Nominal Compositions of Stainless Steels. Appendix 2: Etching Techniques for Stainless Steel Welds. Author Index. Subject Index.

A review of laser welding techniques for magnesium alloys

2005-10-03

X. Cao , Mohammad Jahazi , J.-P. Immarigeon +1 more

Cross-Sectional Mapping of Residual Stresses by Measuring the Surface Contour After a Cut

2000-11-03

Michael B. Prime

A powerful new method for residual stress measurement is presented. A part is cut in two, and the contour, or profile, of the resulting new surface is measured to determine … A powerful new method for residual stress measurement is presented. A part is cut in two, and the contour, or profile, of the resulting new surface is measured to determine the displacements caused by release of the residual stresses. Analytically, for example using a finite element model, the opposite of the measured contour is applied to the surface as a displacement boundary condition. By Bueckner’s superposition principle, this calculation gives the original residual stresses normal to the plane of the cut. This “contour method” is more powerful than other relaxation methods because it can determine an arbitrary cross-sectional area map of residual stress, yet more simple because the stresses can be determined directly from the data without a tedious inversion technique. The new method is verified with a numerical simulation, then experimentally validated on a steel beam with a known residual stress profile.

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Measurement of Non-Uniform Residual Stresses Using the Hole-Drilling Method. Part I—Stress Calculation Procedures

1988-10-01

G. S. Schajer

The Incremental Strain, Average Stress, Power Series, and Integral methods are examined as procedures for determining non-uniform residual stress fields using strain relaxation data from the hole drilling method. Some … The Incremental Strain, Average Stress, Power Series, and Integral methods are examined as procedures for determining non-uniform residual stress fields using strain relaxation data from the hole drilling method. Some theoretical shortcomings in the Incremental Strain and Average Stress methods are described. It is shown that these two traditional methods are in fact approximations of the Integral Method. Theoretical estimates of the errors involved are presented for various stress fields. Also, some simple transformations of stress and strain variables are introduced so as to decouple the stress/strain equations and simplify the numerical solution.

Thermo-mechanical analysis of Wire and Arc Additive Layer Manufacturing process on large multi-layer parts

2011-07-13

Jialuo Ding , Paul A. Colegrove , Jörn Mehnen +4 more

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FEM prediction of welding residual stress and distortion in carbon steel considering phase transformation effects

2008-05-04

Dean Deng

Residual Stress Measurement by Successive Extension of a Slot: The Crack Compliance Method

1999-02-01

Michael B. Prime

This article reviews the technical literature on the determination of a residual stress profile by successive extension of a slot and measurement of the resulting strains or displacements. This technique … This article reviews the technical literature on the determination of a residual stress profile by successive extension of a slot and measurement of the resulting strains or displacements. This technique is known variously in the literature as the crack compliance method, the successive cracking method, the slotting method, and a fracture mechanics based approach. The article briefly summarizes the chronological development of this method and then, to facilitate more detailed review, defines the components that make up the method. The theory section of the article first considers forward method solutions including fracture mechanics, finite element, analytical, and body force methods. Then it examines inverse solutions, including incremental inverses and series expansions. Next, the article reviews all experimental applications of the crack compliance method. Aspects reviewed include the specimen geometry and material, the details of making the slot, the deformation measurement, and the theoretical solutions used to solve for stress. Finally, the article makes a brief qualitative comparison between crack compliance and other residual stress measurement methods. In many situations, the crack compliance method offers several advantages over other methods: improved resolution of residual stress variation with depth; the ability to measure both small and very large parts; measurement of stress intensity factor caused by residual stress; measurement of crack closure stresses; increased sensitivity over other material removal methods; and the ability to measure non-crystalline materials. This review article contains 77 references.

INCONEL 718: A solidification diagram

1989-10-01

Gerald Albert Knorovsky , Roman Cieślak , T.J. Headley +2 more

FINITE ELEMENT MODELING AND SIMULATION OF WELDING PART 1: INCREASED COMPLEXITY

2001-02-01

Lars‐Erik Lindgren

Abstract Simulation of welding has advanced from the analysis of laboratory setups to real engineering applications during the last three decades. This development is outlined and the directions for future … Abstract Simulation of welding has advanced from the analysis of laboratory setups to real engineering applications during the last three decades. This development is outlined and the directions for future research are summarized in this review, which consists of three parts. This part shows that the increased complexity of the models gives a better description of the engineering applications. The important development of material modeling and computational efficiency are outlined in Parts 2 and 3, respectively.

A parametric study of residual stresses in multi-pass butt-welded stainless steel pipes

1998-01-01

B. Brickstad , B. L. Josefson

Methods of measuring residual stresses in components

2011-09-11

N.S. Rossini , Michele Dassisti , K.Y. Benyounis +1 more

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Residual stress. Part 1 – Measurement techniques

2001-04-01

Philip J. Withers , H. K. D. H. Bhadeshia

AbstractResidual stress is that which remains in a body that is stationary and at equilibrium with its surroundings. It can be very detrimental to the performance of a material or … AbstractResidual stress is that which remains in a body that is stationary and at equilibrium with its surroundings. It can be very detrimental to the performance of a material or the life of a component. Alternatively, beneficial residual stresses can be introduced deliberately. Residual stresses are more difficult to predict than the in-service stresses on which they superimpose. For this reason, it is important to have reliable methods for the measurement of these stresses and to understand the level of information they can provide. In this paper, which is the first part of a two part overview, the effect of residual stresses on fatigue lifetimes and structural integrity are first summarised, followed by the definition and measurement of residual stresses. Different types of stress are characterised according to the characteristic length scale over which they self-equilibrate. By comparing this length to the gauge volume of each technique, the capability of a range of techniques is assessed. In the second part of the overview, the different nature and origins of residual stress for various classes of material are examined.

Effect of laser welding parameters on the heat input and weld-bead profile

2005-02-25

K.Y. Benyounis , A.G. Olabi , M.S.J. Hashmi

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Techniques of modern structural geology

1986-05-01

Roddy V. Amenta

Computer modeling of heat flow in welds

1986-09-01

John Goldak , M.J. Bibby , Jeffrey Moore +2 more

The role of recoil pressure in energy balance during laser materials processing

1997-09-21

Vladimir V. Semak , Akira Matsunawa

A theoretical analysis of the energy balance in the laser - metal interaction zone is carried out. The heat transfer due to the recoil-pressure-induced melt flow is taken into consideration. … A theoretical analysis of the energy balance in the laser - metal interaction zone is carried out. The heat transfer due to the recoil-pressure-induced melt flow is taken into consideration. It is shown that, for the absorbed laser intensities typical in welding and cutting, the recoil pressure induces high-velocity melt-flow ejection from the interaction zone. This melt flow carries away from the interaction zone a significant portion of the absorbed laser intensity (about 70 - 90% at low laser intensities); thus, convection-related terms can be ignored neither in calculations of the energy balance in the interaction zone nor in calculations of the thermal field in the vicinity of the weld pool or cutting front.

Assessing and comparing influencing factors of residual stresses in selective laser melting using a novel analysis method

2012-03-08

Jean‐Pierre Kruth , Jan Deckers , Evren Yasa +1 more

During selective laser melting, the irradiated material experiences large temperature fluctuations in a short time which causes unwanted thermal stresses. In order to assess thermal stresses in a simple and … During selective laser melting, the irradiated material experiences large temperature fluctuations in a short time which causes unwanted thermal stresses. In order to assess thermal stresses in a simple and fast way, a new pragmatic method is developed, namely the bridge curvature method. The bridge curvature method is used to assess and qualitatively compare the influence of different laser scan patterns, laser parameter settings and more fundamental process changes on residual stresses. The results from the experiments, as well as the findings from literature, lead to two general conclusions: changes that reduce the high temperature gradient, like using short scan vectors and preheating of the base plate, reduce the thermal stresses. And, thermal stresses in a particular direction can be reduced by optimal choice of the orientation of scan vectors. The experiments indicate the reliability of the bridge curvature method. Statistical analysis is used to check the repeatability of the method and to quantify the uncertainties during measurement.

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Nickel based superalloy welding practices for industrial gas turbine applications

2004-02-01

Monika Henderson , D.J. Arrell , Ragnar Larsson +2 more

The continued drive for increased efficiency, performance and reduced costs for industrial gas turbine engines demands extended use of high strength-high temperature capability materials, such as nickel based superalloys. To … The continued drive for increased efficiency, performance and reduced costs for industrial gas turbine engines demands extended use of high strength-high temperature capability materials, such as nickel based superalloys. To satisfy the requirements of the component design and manufacturing engineers, these materials must be capable of being welded in a satisfactory manner. The present paper describes the characteristic defects found as a result of welding the more difficult, highly alloyed materials and reviews a number of welding processes used in the manufacture and repair of nickel alloy components. These include gas tungsten arc (GTA) and electron beam (EB) welding, laser powder deposition and friction welding. Many of the more dilute nickel based alloys are readily weldable using conventional GTA processes; however, high strength, precipitation hardened materials are prone to heat affected zone and strain age cracking defect formation. A number of factors are found to affect the propensity for defects: composition (aluminium and titanium content), grain size, pre- and post-weld heat treatment, as well as the welding process itself (control of heat input and traverse speed). Process parameter identification is still largely empirical and a fuller understanding of the joining processes is dependent upon the development and application of more sophisticated numerical modelling techniques.

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Numerical simulation of temperature field and residual stress in multi-pass welds in stainless steel pipe and comparison with experimental measurements

2005-10-15

Dean Deng , Hidekazu Murakawa

A model of deep penetration laser welding based on calculation of the keyhole profile

1994-09-14

Alexander Kaplan

A model describing the process of deep-penetration laser welding has been developed by calculating the keyhole profile using a point-by-point determination of the energy balance at the keyhole wall. A … A model describing the process of deep-penetration laser welding has been developed by calculating the keyhole profile using a point-by-point determination of the energy balance at the keyhole wall. A formula for heat conduction was derived from the model of a moving line source of heat. The various absorption mechanisms were modelled. The corresponding absorbed power transferred to the keyhole wall balances the conduction losses, which yields the local inclination of the wall. The thermodynamics and the flow of metal vapour inside the keyhole have been calculated. Accordingly, beam damping due to the plasma plume above the workpiece and the mean plasma absorption coefficient in the keyhole could be estimated. The keyhole profile tends to a geometry that distributes the major part of the beam to the front wall owing to higher conduction losses at the upstream side. The reasons for decreasing energy absorption with increasing welding speed are discussed.

Characterisation of dissimilar joints in laser welding of steel–kovar, copper–steel and copper–aluminium

2004-05-11

Tuan-Anh Mai , A.C. Spowage

Prediction of welding distortion and residual stress in a thin plate butt-welded joint

2008-01-30

Dean Deng , Hidekazu Murakawa

Optimization of different welding processes using statistical and numerical approaches – A reference guide

2007-05-24

K.Y. Benyounis , A.G. Olabi

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Precision Determination of Lattice Constants

1935-10-01

Eric R. Jette , F. Foote

In Part I the theoretical and experimental conditions which must be satisfied in order to determine lattice constants with a precision of a few parts per hundred thousand are discussed … In Part I the theoretical and experimental conditions which must be satisfied in order to determine lattice constants with a precision of a few parts per hundred thousand are discussed with particular application to the symmetrical focusing type of camera. Cohen's method of calculation of lattice constants for the elimination of ``drift'' and experimental errors is applied. Methods are developed for the evaluation of standard errors and fiduciary limits of results from a single film and from a set of films. The usefulness of x-ray targets made of alloys rather than pure elements for the purpose of securing a larger number and better distribution of lines is indicated. The influence of the number and Miller indices of diffraction lines on the values of lattice constants in noncubic systems is shown. The importance of the methods of sample preparation for precision work is emphasized. In Part II, precision measurements on Al, Ni, Ag, Au, Si, Fe, Mo, W, Mg, Zn, Cd, Sb, Bi and Sn are reported for materials of a high degree of purity. The fiduciary limits of these lattice constants vary between 2 and 7 parts per hundred thousand and are so chosen that the probability of the correct value lying between the stated limits is 19 out of 20.

Heat treating and melting material with a scanning laser or electron beam

1977-09-01

H. E. Cline , T. R. Anthony

A thermal analysis for laser heating and melting materials is derived for a Gaussian source moving at a constant velocity. The resulting temperature distribution, cooling rate distribution, and depth of … A thermal analysis for laser heating and melting materials is derived for a Gaussian source moving at a constant velocity. The resulting temperature distribution, cooling rate distribution, and depth of melting are related to the laser spot size, velocity, and power level. As the power is increased to heat the liquid above the boiling point, a transition to deep penetration welding is described. Calculations are presented for 304-stainless steel which are in agreement with experiment.

The application of electron beam welding for the joining of dissimilar metals: an overview

1996-05-01

Zhenzhong Sun , Risto Karppi

A new finite element model for welding heat sources

1984-06-01

John Goldak , Aditya Chakravarti , Malcolm Bibby

Introduction to the Physical Metallurgy of Welding

1992-01-01

K. E. Easterling

Laser welding of Ti6Al4V titanium alloys

2008-09-07

Erhan Akman , A. Demir , Timur Canel +1 more

Heat transfer and fluid flow during keyhole mode laser welding of tantalum, Ti–6Al–4V, 304L stainless steel and vanadium

2007-08-30

Ram Naresh , J. W. Elmer , Todd Palmer +1 more

Because of the complexity of several simultaneous physical processes, most heat transfer models of keyhole mode laser welding require some simplifications to make the calculations tractable. The simplifications often limit … Because of the complexity of several simultaneous physical processes, most heat transfer models of keyhole mode laser welding require some simplifications to make the calculations tractable. The simplifications often limit the applicability of each model to the specific materials systems for which the model is developed. In this work, a rigorous, yet computationally efficient, keyhole model is developed and tested on tantalum, Ti–6Al–4V, 304L stainless steel and vanadium. Unlike previous models, this one combines an existing model to calculate keyhole shape and size with numerical fluid flow and heat transfer calculations in the weld pool. The calculations of the keyhole profile involved a point-by-point heat balance at the keyhole walls considering multiple reflections of the laser beam in the vapour cavity. The equations of conservation of mass, momentum and energy are then solved in three dimensions assuming that the temperatures at the keyhole wall reach the boiling point of the different metals or alloys. A turbulence model based on Prandtl's mixing length hypothesis was used to estimate the effective viscosity and thermal conductivity in the liquid region. The calculated weld cross-sections agreed well with the experimental results for each metal and alloy system examined here. In each case, the weld pool geometry was affected by the thermal diffusivity, absorption coefficient, and the melting and boiling points, among the various physical properties of the alloy. The model was also used to better understand solidification phenomena and calculate the solidification parameters at the trailing edge of the weld pool. These calculations indicate that the solidification structure became less dendritic and coarser with decreasing weld velocities over the range of speeds investigated in this study. Overall, the keyhole weld model provides satisfactory simulations of the weld geometries and solidification sub-structures for diverse engineering metals and alloys.

Residual stress and its role in failure

2007-11-27

Philip J. Withers

Our safety, comfort and peace of mind are heavily dependent upon our capability to prevent, predict or postpone the failure of components and structures on the basis of sound physical … Our safety, comfort and peace of mind are heavily dependent upon our capability to prevent, predict or postpone the failure of components and structures on the basis of sound physical principles. While the external loadings acting on a material or component are clearly important, There are other contributory factors including unfavourable materials microstructure, pre-existing defects and residual stresses. Residual stresses can add to, or subtract from, the applied stresses and so when unexpected failure occurs it is often because residual stresses have combined critically with the applied stresses, or because together with the presence of undetected defects they have dangerously lowered the applied stress at which failure will occur. Consequently it is important that the origins of residual stress are understood, opportunities for removing harmful or introducing beneficial residual stresses recognized, their evolution in-service predicted, their influence on failure processes understood and safe structural integrity assessments made, so as to either remove the part prior to failure, or to take corrective action to extend life. This paper reviews the progress in these aspects in the light of the basic failure mechanisms.

Residual stress. Part 2 – Nature and origins

2001-04-01

Philip J. Withers , H. K. D. H. Bhadeshia

AbstractAbstractResidual stress is that which remains in a body that is stationary and at equilibrium with its surroundings. It can be detrimental when it reduces the tolerance of the material … AbstractAbstractResidual stress is that which remains in a body that is stationary and at equilibrium with its surroundings. It can be detrimental when it reduces the tolerance of the material to an externally applied force, as is the case with welded joints. On the other hand, it can be exploited to design materials or components which are resistant to damage, toughened glass being a good example. This paper, the second part of a two part overview, the first part having been devoted to measurement techniques, examines the nature and origins of residual stresses across a range of scales. This extends from the long range residual stress fields in engineering components and welded structures, through the interphase stresses present in composites and coatings, to the microscale interactions of phase transformations with local stresses.

Initial reports of the deep sea drilling project

1971-02-01

Roland von Huene

Welding Metallurgy and Weldability

2014-11-14

John C. Lippold

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Ameliorated longitudinal critically refracted—Attenuation velocity method for welding residual stress measurement

2017-03-24

Qimeng Zhu , Jia Chen , Guoqing Gou +2 more

Cold metal transfer (CMT) technology - An overview

2017-09-01

S. Panneer Selvi , A. Vishvaksenan , E. Rajasekar

Cold Metal Transfer technology has revolutionized the welding of dissimilar metals and thicker materials by producing improved weld bead aesthetics with controlled metal deposition and low heat-input. In this study, … Cold Metal Transfer technology has revolutionized the welding of dissimilar metals and thicker materials by producing improved weld bead aesthetics with controlled metal deposition and low heat-input. In this study, the process, weld combinations, laser-CMT hybrid welding and applications of CMT welding are critically reviewed. Microstructure and other weld characteristics have been discussed at length for various base metal combinations. Particularly, the welding of aluminium and steel with better results has been possible with CMT Welding. The results reviewed in this article indicate that the CMT-Laser hybrid welding is more preferable to Laser or Laser hybrid welding. CMT welding has found applications in automobile industries, defence sectors and power plants as a method of additive manufacturing.

The Theory of Moving Sources of Heat and Its Application to Metal Treatments

1946-11-01

Daniel Rosenthal

Abstract The theory of moving sources of heat has been instrumental in providing the welding engineer with a scientific criterion of weldability of steels. The author outlines briefly the fundamentals … Abstract The theory of moving sources of heat has been instrumental in providing the welding engineer with a scientific criterion of weldability of steels. The author outlines briefly the fundamentals of this theory and derives appropriate solutions for linear, two- and three-dimensional flow of heat in solids of infinite size or bounded by planes. Point, linear, and plane sources of heat are examined. The solutions obtained are then applied to welding problems. It is shown that these solutions are in good agreement with the experimental results, and that they afford a close analysis of the factors governing the heat flow in welding. The most interesting result of the theory, however, is the derivation of a single formula capable of predicting the time and rate of cooling with a fairly good accuracy for a wide variety of thicknesses of steel, ranges of temperature, and welding conditions. An attempt has been made also to show how this theory could be applied to other problems of metal treatment, such as rate of extrusion in continuous casting, or control of flame-hardening and continuous quenching operations.

Temperature fields produced by traveling distributed heat sources

1983-12-01

Thomas W. Eagar , N. S. Tsai

The solution of a traveling distributed heat source on a semi-infinite plate provides information about both the size and the shape of arc weld pools. The results indicate that both … The solution of a traveling distributed heat source on a semi-infinite plate provides information about both the size and the shape of arc weld pools. The results indicate that both welding process variables (current, arc length and travel speed) and material parameters (thermal diffusivity) have significant effects on weld shape. The theoretical predictions are compared with experimental results on carbon steels, stainless steel, titanium and aluminum with good agreement. 25 references, 23 figures, 1 table.

Structural and Residual Stress Analysis by Nondestructive Methods

1997-01-01

Viktor Hauk , W. A. Theiner

Residual Stress

1987-01-01

I. C. Noyan , Jerome B. Cohen

Structural and residual stress analysis by nondestructive methods : evaluation, application, assessment

1997-01-01

V. Hauk , Herfried Behnken

Duplex Stainless Steels Microstructure, Properties and Applications

1998-04-01

Robert Neil Gunn

Developments, grades and specifications Alloy design Microstructure Forming and machining Physical and mechanical properties Corrosion Stress corrosion cracking Welding metallurgy Welding processes Weld properties Non-destructive testing of welds Applications Service … Developments, grades and specifications Alloy design Microstructure Forming and machining Physical and mechanical properties Corrosion Stress corrosion cracking Welding metallurgy Welding processes Weld properties Non-destructive testing of welds Applications Service experience.

Mechanical property curve of resistance spot welding for on-line monitoring of the welding quality

2025-06-26

Enpei Zhao , Jiajian Meng , Mingming Lu +6 more | Journal of Manufacturing Processes

Comparative Analysis of Plasma and Tig Welding on Mild Steel Bars

2025-06-25

Comfort Deon Nkalanga , Pálinkás Sándor | Materials science forum

Plasma and TIG arc welding they are similar welding processes for the base of plasma welding is tig welding. The main purpose of this paper to come to a detailed … Plasma and TIG arc welding they are similar welding processes for the base of plasma welding is tig welding. The main purpose of this paper to come to a detailed conclusion based on a comparative analysis of both welding processes. The analysis is done steel bars each applied with the particular welding technique either plasma or tig welding. The principles of each welding procedure are discussed on how they welding is carried out, the mechanics and the technological functions of the welding devices are also discussed. The time required to complete a weld, the amount of current used. Impact on the steel is investigated caused by each welding processes. The welded joints are tested for bending and how much they elongate when under bending stress. The welded joints are done as butt welds for both of the grouped steel bars. These welding processes are used in industries where precision is of great importance like aerospace, design of industrial machinery, ship construction and Petro chemical industries. The concluded results of this paper will be of great contribution to the manufacturing industries because they would be able to know which welding process is best for which particular case or both must be used in order to achieve an ideal outcome. Keywords: Plasma and Tungsten inert gas TIG welding arc, tensile mild Steel bars, bending, butt weld, Amount of current, elongation.

The mechanism of molten pool dynamics in laser-MIG hybrid welding of titanium-aluminum dissimilar alloys

2025-06-25

Xiongfeng Zhou , Yan Zhang , Pengcheng Guo +3 more | Optics & Laser Technology

Numerical Simulation of Residual Stresses Induced by MIG Welding Considering Initial Conditions

2025-06-25

Mahmood Hasan Alhafadhi , Mohammed Ahmed Shehab , Masar Alsigar +4 more | Materials science forum

This research describes the numerical simulation of welding residual stresses (WRS)induced by Metal Inert Gas (MIG) welding, explicitly emphasizing the role of initial conditions. MIGwelding is a widely and commonly … This research describes the numerical simulation of welding residual stresses (WRS)induced by Metal Inert Gas (MIG) welding, explicitly emphasizing the role of initial conditions. MIGwelding is a widely and commonly adopted process in different industries due to its strength andefficiency; however, it generates welding residual stresses that can influence welded components'structural integrity and performance. The numerical simulation calculates various initial conditions,such as pre-existing stresses, temperature variations, material characteristics, and so on, to model thewelding process accurately and with accurate results. By using finite element analysis or numericalsimulation, this study predicts and estimates the intensity and distribution of welding residual stressesin welded joints for optimizing welding parameters to reduce adverse effects on welded structures. Acomparison between non-destructive testing, such as X-ray diffraction (XRD) measurements andnumerical simulations, shows good agreement in assessing residual stresses and validating theaccuracy of the numerical model. Based on the numerical simulation software, the numericalcalculation and analysis of residual stress field under different preheating temperatures for pipewelding were carried out in this paper. The effects of different preheating temperatures on post-weldresidual stress were mainly studied. This approach enables comprehensive calculation of stressdistributions, including axial and hoop stresses across different weld pipes on the surface orientations,offering insights into critical stress areas and potential failure points. These findings demonstrate theutility of numerical simulations as an effective tool for enhancing welded structure design.

Microstructure and Mechanical Properties of Dissimilar Metal Welded Joints for Nuclear Applications Using Laser Welding with Dissimilar Filler Wire Addition

2025-06-24

Jiecai Feng , Longbin Tao , Hongfei Liu +6 more | Metals and Materials International

Tensile and Microstructural Characteristics of AISI 304- Inconel 718 Welded Joint: Effect of Heat Treatment

2025-06-24

Amrita Agarwal , Aarav Shrenik Dodhia , Avaneesh Rajesh Kulkarni +1 more | Journal of The Institution of Engineers (India) Series C

Optimizing welding angle for enhancing hybrid welding seam quality

2025-06-24

Lingxiao Song , Peilei Zhang , Zufa Li +4 more | Welding in the World

Effects of Ultrasonic Impact on Residual Stress, Microstructure, and Electrochemical Properties of Q690 Welded Joint

2025-06-23

Bangping Gu , Chengjian Yin , Liqiang Gao +6 more | Journal of Materials Engineering and Performance

Exploring Trace Mg Microalloying Impact on Corrosion Mechanism of X70 Steel

2025-06-22

Tianqi Chen , Zhiyi Wang , Qinglin Li +6 more | Metallurgical and Materials Transactions A

TIG-based hybrid arc welding: a review

2025-06-22

Siyu Zhang , Honglei Zhao , Yiwen Li +3 more | The International Journal of Advanced Manufacturing Technology

Study on Microstructure and Stress Distribution of Laser-GTA Narrow Gap Welding Joint of Ti-6Al-4V Titanium Alloy in Medium Plate

2025-06-21

Zhigang Cheng , Qiang Lang , Zhaodong Zhang +2 more | Materials

Traditional narrow gap welding of thick titanium alloy plates easily produces dynamic molten pool flow instability, poor sidewall fusion, and excessive residual stress after welding, which leads to defects such … Traditional narrow gap welding of thick titanium alloy plates easily produces dynamic molten pool flow instability, poor sidewall fusion, and excessive residual stress after welding, which leads to defects such as pores, cracks, and large welding deformations. In view of the above problems, this study takes 16-mm-thick TC4 titanium alloy as the research object, uses low-power pulsed laser-GTA flexible heat source welding technology, and uses the flexible regulation of space between the laser, arc, and wire to promote good fusion of the molten pool and side wall metal. By implementing instant ultrasonic impact treatment on the weld surface, the residual stress of the welded specimen is controlled within a certain range to reduce deformation after welding. The results show that the new welding process makes the joint stable, the side wall is well fused, and there are no defects such as pores and cracks. The weld zone is composed of a large number of α′ martensites interlaced with each other to form a basketweave structure. The tensile fracture of the joint occurs at the base metal. The joint tensile strength is 870 MPa, and the elongation after fracture can reach 17.1%, which is 92.4% of that of the base metal. The impact toughness at the weld is 35 J/cm2, reaching 81.8% of that of the base metal. After applying ultrasound, the average residual stress decreased by 96% and the peak residual stress decreased by 94.8% within 10 mm from the weld toe. The average residual stress decreased by 95% and the peak residual stress decreased by 95.5% within 10 mm from the weld root. The residual stress on the surface of the whole welded test plate could be controlled within 200 MPa. Finally, a high-performance thick Ti-alloy plate welded joint with good forming and low residual stress was obtained.

Influence of Post-Heat Treatment on the Tensile Strength and Microstructure of Metal Inert Gas Dissimilar Welded Joints

2025-06-20

Van–Thuc Nguyen , Thanh Tan Nguyen , Van Huong Hoang +7 more | Crystals

Taguchi and post-heat treatment methods have been used in this study to optimize the metal inert gas (MIG) welding joints between SUS304 austenite stainless steel and plain carbon SS400 steel … Taguchi and post-heat treatment methods have been used in this study to optimize the metal inert gas (MIG) welding joints between SUS304 austenite stainless steel and plain carbon SS400 steel using AWS ER 308L filler wire. The dissimilar welding joints’ microstructure and tensile strength have been examined. The findings show that the fast cooling of the weld joint and the ferrite-forming element of the filler wire cause the dendrites’ δ-ferrite phase to emerge on both the weld bead and the heat-affected zone (HAZ) of the SUS304 side. The stickout parameter has the largest impact on the ultimate tensile strength (UTS), next to the welding speed, welding voltage, and welding current, due to the strong impact of the heat distribution. The optimal welding parameters are a welding current of 105 A, a welding voltage of 14.5 V, a stickout of 12 mm, and a welding speed of 420 mm/min, producing the UTS value of 445.3 MPa, which is close to the predicted value of 469.2 ± 53.6 MPa. Post-heat treatment with an annealing temperature that is lower than 700 °C could improve the optimized weld joints’ strength by up to 5%. The findings may provide a more realistic understanding of the dissimilar welding technology.

Decoding Microstructural Heterogeneity and Mechanical Anomalies in GMAW of AISI 1010 Steel through Multi-Technique Characterization

2025-06-20

Mohammad Jellur Rahman

<title>Abstract</title> This study explores the microstructural evolution and mechanical behavior of Gas Metal Arc Welded (GMAW) joints in AISI 1010 low-carbon steel to assess weld integrity and performance. A comprehensive … <title>Abstract</title> This study explores the microstructural evolution and mechanical behavior of Gas Metal Arc Welded (GMAW) joints in AISI 1010 low-carbon steel to assess weld integrity and performance. A comprehensive evaluation combining optical microscopy, Rockwell B hardness profiling, Optical Emission Spectroscopy (OES), tensile testing, Charpy impact testing, and Scanning Electron Microscopy (SEM) was conducted. The weld zone (WZ) exhibited dendritic solidification and recorded the highest hardness, while the heat-affected zone (HAZ) showed a significant reduction due to thermal softening and grain coarsening. Tensile testing revealed a peak strength of 461.14 MPa, with fracture localized in the WZ, indicating it as the weakest region under axial loading despite its higher hardness. Face bend testing confirmed overall ductility, although surface cracking and delamination at the weld interface indicated incomplete fusion and internal discontinuities. SEM analysis revealed mixed-mode fracture behavior, including ductile dimples, cleavage planes, and intergranular tearing. Charpy impact testing at sub-zero temperatures further confirmed reduced fracture toughness in the fusion zone. These findings underscore that while GMAW can produce structurally sound joints in AISI 1010 steel, localized heterogeneities—particularly within the WZ—may compromise reliability. With optimized process control and defect monitoring, GMAW remains a viable and cost-effective welding solution for low-carbon steel structural applications.

Study on the Calculation of Heat-Affected Zone Width in Girth Weld of large-scale X80M Pipeline

2025-06-20

Ze Yun , Yan Li , Pengchao Chen +3 more | International Journal of Pressure Vessels and Piping

Mechanical Properties of Repaired Welded Pipe Joints Made of Heat-Resistant Steel P92

2025-06-19

Filip Vučetić , Branislav Djordjević , Dorin Radu +4 more | Materials

This research provides a detailed investigation into the mechanical properties and microstructural evolution of heat-resistant steel P92 subjected to both initial (i) welding procedures and simulated (ii) repair welding. The … This research provides a detailed investigation into the mechanical properties and microstructural evolution of heat-resistant steel P92 subjected to both initial (i) welding procedures and simulated (ii) repair welding. The study addresses the influence of critical welding parameters, including preheating temperature, heat input, and post-weld heat treatment (PWHT), with a particular emphasis on the metallurgical consequences arising from the application of repair welding thermal cycles. Through the analysis of three welding probes-initially welded pipes using the PF (vertical upwards) and PC (horizontal-vertical) welding positions, and a PF-welded pipe undergoing a simulated repair welding (also in the PF position)-the research compares microstructure in the parent material (PM), weld metal (WM), and heat-affected zone (HAZ). Recognizing the practical limitations and challenges associated with achieving complete removal of the original WM under the limited (in-field) repair welding, this study provides a comprehensive comparative analysis of uniaxial tensile properties, impact toughness evaluated via Charpy V-notch testing, and microhardness measurements conducted at room temperature. Furthermore, the research critically analyzes the influence of the complex thermal cycles experienced during both the initial welding and repair welding procedures to elucidate the practical application limits of this high-alloyed, heat-resistant P92 steel in demanding service conditions.

Numerical simulation to determine the suitable welding parameters for the butt joint between DP600 and X5CrNi18-10 steel pipes

2025-06-19

| Journal of Science and Technology of Metal

Influence of graphene on inclusions of slag–free self–shielded flux–cored arc welding layer

2025-06-19

Dashuang Liu , C-Q. Li , Xionghui Li +4 more | Materials Science and Technology

The slag-free self-shielded flux-cored wire was modified by including graphene at concentrations of 0.00 wt.%, 0.15 wt.%, and 0.30 wt.%. The study's findings suggest that the primary constituents present in … The slag-free self-shielded flux-cored wire was modified by including graphene at concentrations of 0.00 wt.%, 0.15 wt.%, and 0.30 wt.%. The study's findings suggest that the primary constituents present in the deposited metal are AlN, Al 2 O 3 , Al 2 O 3 ·MgO, MgO, and MnS. The graphene reduces the average particle size from 2.59 μm to 2.13 μm as the graphene content increases. The inclusion 2 count reduces from 1599 to 1527 when graphene is introduced at a concentration of 0.30 wt.%. The fracture mode shown by the deposited metal is characterized by brittle fracture. Without graphene, the impact toughness value is measured to be 3.2 J/cm 2 . At a graphene addition of 0.3 wt.%, the impact toughness exhibits a rise to 7.2 J/cm 2 .

Effect of Thermal Pulse Frequency on Microstructural and Mechanical Properties of Inconel 718 Superalloy by Double Pulse Metal Inert Gas Welding

2025-06-19

M. Shantharaj , T. Rajasekaran | Journal of Materials Engineering and Performance

Arc instability in hybrid laser-GMAW welding process using Ni based filler wire NiCrMo-4

2025-06-19

Zuchao Zhu , Yu Shi , Zhang Gang +5 more | Journal of Manufacturing Processes

Improvement of metal transfer stability in large angle wire feeding GTAW by vibration wire feeding

2025-06-19

Jinsheng Liu , Yi Gao , Hongming Gao | Journal of Manufacturing Processes

REPAIR METHOD FOR CORRODED ANGLE STEEL USING CFRP BY VARTM TECHNIQUE

2025-06-19

Shogo Higuchi , Yosuke Yamazaki , Shintaro Tahara +2 more | AIJ Journal of Technology and Design

A Study on Mechanical Properties and Microstructure of Welded Joints in EH40 Steel with High Heat Input Welding

2025-06-19

Tao Wen , Huixin Quan , Pengyan Zhang +2 more | Journal of Materials Engineering and Performance

Welding Image Data Augmentation Method Based on LRGAN Model

2025-06-19

Ying Wang , Zhe Dai , Qiang Zhang +1 more | Applied Sciences

This study focuses on the data bottleneck issue in the training of deep learning models during the intelligent welding control process and proposes an improved model called LRGAN (loss reconstruction … This study focuses on the data bottleneck issue in the training of deep learning models during the intelligent welding control process and proposes an improved model called LRGAN (loss reconstruction generative adversarial networks). First, a five-layer spectral normalization neural network was designed as the discriminator of the model. By incorporating the least squares loss function, the gradients of the model parameters were constrained within a reasonable range, which not only accelerated the convergence process but also effectively limited drastic changes in model parameters, alleviating the vanishing gradient problem. Next, a nine-layer residual structure was introduced in the generator to optimize the training of deep networks, preventing the mode collapse issue caused by the increase in the number of layers. The final experimental results show that the proposed LRGAN model outperforms other generative models in terms of evaluation metrics such as peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and Fréchet inception distance (FID). It provides an effective solution to the small sample problem in the intelligent welding control process.

Probing the influence of rotation parameters on submerged arc weld characteristics

2025-06-19

Adapa Mahanth Kumar , Polamuri Sudheer Kumar , Venkaiah Nasina +1 more | Welding International

Environmental impact assessment of welding and the parameter optimization using neural network

2025-06-19

Yun Liu , Haihong Huang , Lei Li +2 more | The International Journal of Advanced Manufacturing Technology

MICROSTRUCTURAL ASSESMENT OF FERRITE-AUSTENITE RATIO AND ITS INFLUENCE ON CORROSION AND MECHANICAL PERFORMANCE OF DSS 2205 WELDS UNDER H2S-RICH REAL ENVIRONMENT

2025-06-18

Bryan Ramiro Rodríguez-Vargas , Giulia Stornelli , H.M. Hdz-García +2 more | Materials Today Communications

Automated weld defect detection using YOLOv8 algorithm

2025-06-18

K. Gajalakshmi , Sivaneasan Bala Krishnan , S. Saravanan | Welding International

A Data-Driven Approach for Energy Consumption Modeling and Optimization of Welding Robot Systems

2025-06-18

Mingyang Pan , Bingqi Jia , Lei Zhang +2 more | Machines

Welding robots play a crucial role in manufacturing industries, where minimizing energy consumption (EC) is increasingly important for enhancing efficiency and reducing operational costs. This study presents a data-driven approach … Welding robots play a crucial role in manufacturing industries, where minimizing energy consumption (EC) is increasingly important for enhancing efficiency and reducing operational costs. This study presents a data-driven approach to model and optimize EC in welding robot systems, utilizing a dataset generated from real-world measurements of robot EC during various motions and integrated with trajectory data. A predictive model was developed using an extreme gradient boosting (XGBoost) regression technique focused on joint torque data, which achieved a mean absolute percentage error (MAPE) of 1.86%. Furthermore, trajectory optimization was achieved by adjusting the spatial position of the workpiece, effectively reducing EC. To solve the optimization problem, an improved whale optimization algorithm (IWOA) was employed. Experimental validations with a welding robot demonstrate that the proposed method not only accurately predicted EC with a MAPE of 2.66% but also reduced the robot system’s EC by 6.72%, outperforming the traditional method focused solely on joint motor EC, which achieved a 4.08% reduction. These results confirm the efficacy of the proposed approach, underscoring its potential for broad application in robotic systems to achieve significant energy savings.

Investigation of Surface Welding Defects in EN AW 5083 HO Aluminum Plates Joined by Robotic GMAW Butt Welding Using Non-Destructive Testing Methods

2025-06-18

Celalettin Baykara , Ahmet Oral | Research Square (Research Square)

<title>Abstract</title> The aim of this study is to systematically investigate the superficial weld defects that may occur after welding in 1.75 mm thick EN AW 5083 HO aluminium alloy sheets, … <title>Abstract</title> The aim of this study is to systematically investigate the superficial weld defects that may occur after welding in 1.75 mm thick EN AW 5083 HO aluminium alloy sheets, which have high corrosion resistance due to their high magnesium content, using butt welding configuration and Gas Metal Arc Welding (GMAW) method. The ultimate goal is to determine the best welding parameters to improve the structural performance and service reliability of aluminium welded structures, especially in marine engineering applications. In the experimental study, EN AW 5083 HO aluminium sheets were prepared and then butt welded by robotic GMAW method under variable welding current and welding speed parameters. After welding, non-destructive testing methods such as visual inspection (ISO 17637), liquid penetrant test (ISO 3452-1), radiographic inspection (ISO 17636-1) were applied to the samples. The data obtained were evaluated to detect, classify and quantitatively analyse weld defects such as porosity, weld incompleteness, weld bead defects and surface cracks. The relationship between welding parameters and defect formation was analysed and the most suitable parameters were determined to obtain defect-free welds. The analyses showed a strong relationship between welding parameters and defect formation. High welding current and inappropriate feed rates were associated with increased porosity and lack of fusion; A significant reduction in surface defect rates and an improvement in weld seam quality were achieved with the best weld parameter determined. The results are reported in accordance with the acceptance criteria for aluminium welds specified in ISO 5817 standards.

An inverse method for arc-droplet-pool coupled GMAW simulation based on an iterative current distribution model

2025-06-18

Feng Shi , Hui Jin | International Communications in Heat and Mass Transfer

Microstructure and mechanical properties of 5%Ni steel joints welded by NG-HWTIG welding process

2025-06-18

Zhiqiang Zhang , Zhiwei Zeng , Yingguang Zhu +5 more | International Journal of Pressure Vessels and Piping

Thermal, Metallurgical, and Mechanical Analysis of Single-Pass INC 738 Welded Parts

2025-06-18

Cherif Saib , Salah Amroune , Mohamed-Saïd Chebbah +3 more | Metals

This study presents numerical analyses of the thermal, metallurgical, and mechanical processes involved in welding. The temperature fields were computed by solving the transient heat transfer equation using the ABAQUS/Standard … This study presents numerical analyses of the thermal, metallurgical, and mechanical processes involved in welding. The temperature fields were computed by solving the transient heat transfer equation using the ABAQUS/Standard 2024 finite element solver. Two types of moving heat sources were applied: a surface Gaussian distribution and a volumetric model, both implemented via DFLUX subroutines to simulate welding on butt-jointed plates. The simulation accounted for key welding parameters, including current, voltage, welding speed, and plate dimensions. The thermophysical properties of the INC 738 LC nickel superalloy were used in the model. Solidification characteristics, such as dendritic arm spacing, were estimated based on cooling rates around the weld pool. The model also calculated transverse residual stresses and applied a hot cracking criterion to identify regions vulnerable to cracking. The peak transverse stress, recorded in the heat-affected zone (HAZ), reached 1.1 GPa under Goldak’s heat input model. Additionally, distortions in the welded plates were evaluated for both heat source configurations.

Promising Weld Depth of Penetration by Melting Point Depression Through TiO2 Nano-Flux in Activated TIG Welding of Stainless Steel AISI 304L

2025-06-17

M. Santhosh , A. John Rajan , T. Sampath Kumar +2 more | Transactions of the Indian Institute of Metals

Prediction of welding-induced distortion in stiffened panels using artificial neural networks

2025-06-17

Sang-Jin Kim , Myung-Su Yi , Jung Min Sohn +1 more | Ships and Offshore Structures

"EQUITABLE REMUNERATION" FOR PERFORMERS — THEORETICAL BASIS AND CURRENT PROBLEMS

2025-06-17

Mehti Melikov | Economic Thought journal

The concept of equitable remuneration paid to performers for the use of sound recordings containing their works was introduced by international treaties in the field. The Rome Convention for the … The concept of equitable remuneration paid to performers for the use of sound recordings containing their works was introduced by international treaties in the field. The Rome Convention for the Protection of Performers, Producers of Phonograms and Broadcasting Organisations of 1961 introduced the "right to remuneration", replacing the exclusive right of the performer to authorise the secondary use of their recorded performances. The article examines the transition from an "exclusive right" to the "right to remuneration" in the context of Bulgaria’s cultural industry. The author proposes a categorisation of the phases during which creative products are made and brought to fruition while also tracing the role of performers’ rights throughout each stage of this process. From a business standpoint, achieving equitable remuneration is often put to the test since it is possible for both sides to agree on a lump sum payment. With regard to the perceived weaker position of performers compared to producers, the author critically analyses the scope of performers’ exclusive rights in the Bulgarian Copyright and Neighbouring Rights Act. It is concluded that this law prevents the effective collection and distribution of equitable remuneration for performers in cases of live performances when sound recordings are made and broadcasted on radio or television channels.

Welding of thick Ti-6Al-4V plate via narrow gap oscillating laser tungsten inert gas (NG-OL-TIG) hybrid welding: microstructure and mechanical properties

2025-06-17

Gang Ruan , Chen Shen , Yuelong Zhang +6 more | The International Journal of Advanced Manufacturing Technology

Submerged Arc Welding of S355G10+M Steel: Analyzing Strength, Distortion, Residual Stresses, and Fatigue for Offshore Wind Applications

2025-06-17

Victor Okenyi , Shukri Afazov , Neil J. Mansfield +5 more | Fatigue & Fracture of Engineering Materials & Structures

ABSTRACT This research delves into the material performance of submerged arc‐welded S355G10 +M structural steel for offshore wind turbines, with an emphasis on strength, ductility, hardness, distortion, residual stress, and … ABSTRACT This research delves into the material performance of submerged arc‐welded S355G10 +M structural steel for offshore wind turbines, with an emphasis on strength, ductility, hardness, distortion, residual stress, and fatigue. This was done by conducting experiments and employing modeling tools combined with image analysis. The novelty of this study lies in examining the effects of material properties of S355G10 +M structural steel used in welded offshore wind turbine tower and monopile. The study employed a submerged arc welding (SAW) process on S355G10 +M plates of varying thicknesses by applying double V‐groove and multi‐pass technique. Tensile tests revealed that welded sections exhibit greater ultimate tensile strength than the base material, despite the lower yield strength. In addition, hardness and residual stresses correlate with thickness, and a potential weak point is observed at the heat‐affected zone (HAZ) and base material transition. Angular distortions and axial misalignments after welding, as well as stress concentrations and residual stresses, were found to affect the fatigue performance. It was concluded that the conducted welds have sufficient quality to be exploited into industrial marine applications including offshore wind turbines.

Analysis of residual stress evolution during the entire process manufacturing of pipeline pipe

2025-06-16

Shaocong Qi , Gaochao Yu , Deping Peng +4 more | Journal of Manufacturing Processes

Multi-physics coupled simulation of the thermal-pressure characteristics of hybrid TIG-MIG arc

2025-06-16

Ran Zong , Yinghao Li , Yujiao Zhang +3 more | The International Journal of Advanced Manufacturing Technology

Phase Transformation Kinetics During Post-Weld Heat Treatment in Weldments of C-250 Maraging Steel

2025-06-16

Mauricio Suárez‐Durán , Pablo Reynoso Peitsch , Hernán Svoboda | Materials

Welding of maraging steels leads to a microstructural gradient from base material (BM) to weld metal (WM). During post-weld heat treatment (PWHT) the precipitation and reverted austenite (γr) reactions will … Welding of maraging steels leads to a microstructural gradient from base material (BM) to weld metal (WM). During post-weld heat treatment (PWHT) the precipitation and reverted austenite (γr) reactions will occur defining the mechanical properties. These reactions are affected by the microstructure and local chemical composition of each zone in the "as welded" (AW) condition. This effect has not been clearly described yet nor the evolution of the microstructure. The objective of this work was to analyse the phase transformations at the different zones of the welded joint during the PWHT to explain the microstructure obtained at each zone. Samples of C250 maraging steel were butt-welded by GTAW-P (Gas Tungsten Arc Welding-Pulsed) process without filler material. The AW condition showed an inhomogeneous microhardness profile, associated with a partial precipitation hardening in the subcritical heat affected zone (SC-HAZ) followed by a softening in the intercritical (IC-HAZ) and recrystallized heat affected zone (R-HAZ). A loop-shaped phase was observed between low temperature IC-HAZ and SC-HAZ, associated with γr, as well as microsegregation at the weld metal (WM). The microstructural evolution during PWHT (480 °C) was evaluated on samples treated to different times (1-360 min). Microhardness profile along the welded joint was mostly homogeneous after 5 min of PWHT due to precipitation reaction. The microhardness in the WM was lower than in the rest of the joint due to the depletion of Ni, Ti and Mo in the martensite matrix related with the γr formation. The isothermal kinetics of precipitation reaction at 480 °C was studied using Differential Scanning Calorimetry (DSC), obtaining a JMAK expression. The average microhardness for each weld zone was proposed for monitoring the precipitation during PWHT, showing a different behaviour for the WM. γr in the WM was also quantified and modelled, while in the IC-HAZ tends to increase with PWHT time, affecting the microhardness.

Modelling the keyhole profile in laser welding through energy balance including the local contribution of multiple reflections through the plasma by ray tracing

2025-06-16

Donato Coviello , Antonio D’Angola , Donato Sorgente +1 more | Journal of Manufacturing Processes

Residual Stress Evolution During the Manufacturing of an Aircraft Component

2025-06-16

Walid Jomaa , Kadiata Ba , Julie Lévesque +1 more | Advances in transdisciplinary engineering

This paper proposes a comprehensive analysis of the evolution of the surface residual stress state over the manufacturing stages of generic forged aircraft components. This has been achieved through an … This paper proposes a comprehensive analysis of the evolution of the surface residual stress state over the manufacturing stages of generic forged aircraft components. This has been achieved through an experimental procedure, involving forging of the generic component preforms, heat treatments, and machining operations on Computer Numerical Control milling and lathe centers. Surface residual stresses were measured using X-ray diffraction technique. The results showed a high scatter of surface residual stress measured in the same zone although the machining was done by the same cutting tool and under the same machining conditions. This suggests that the residual stress measured at a specific zone is significantly sensitive to previous and further major material removal such as rough pocketing the components have underwent. Moreover, it was found that the quenching and aging heat treatment drastically modify, not only the machining induced-residual stress state, but also the physical surface characteristics as demonstrated by the shear to normal residual stress ratio and the full width at half maximum of the X-ray diffraction peaks. Conclusively, the findings of this work help both researchers and manufacturers to better understand the challenges related to the design and the manufacturing of structural aircraft components made from forgings.

Towards Automated Algebraic Multigrid Preconditioner Design Using Genetic Programming for Large-Scale Laser Beam Welding Simulations

2025-06-16

Dinesh Parthasarathy , Tommaso Bevilacqua , Martin Lanser +2 more

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Mini Review: Analysis of The Influence of Work Environment on SMAW (Shielded Metal Arc Welding) Results

2025-06-16

Gita Nursafitri , Ari Dwi Nur Indriawan | Sainteknol Jurnal Sains dan Teknologi

This study aimed to systematically investigate the influence of key environmental factors on the quality of Shielded Metal Arc Welding (SMAW) outcomes. The welding process, although widely applied across various … This study aimed to systematically investigate the influence of key environmental factors on the quality of Shielded Metal Arc Welding (SMAW) outcomes. The welding process, although widely applied across various industrial sectors, remains highly sensitive to variations in its surrounding environment. Through a systematic review of previous research, academic articles, and industrial reports, this study identified temperature, air pollution, and ventilation as the most critical environmental variables. Temperature fluctuations were found to cause weld defects such as porosity and cracking. Optimal welding performance was observed within an ambient temperature range of 10°C to 30°C, with several studies suggesting narrower optimal ranges of 15°C to 28°C or 16°C to 27°C. Temperatures below 10°C accelerated weld cooling, increasing the risk of cold cracks, while those above 30°C degraded electrode coatings, leading to porosity. Moreover, airborne contaminants—including Fe₂O₃, MnO, and CO concentrations exceeding 5 mg/m³—were shown to reduce tensile strength by 15% to 20%. Adequate ventilation, particularly using mechanical systems like local exhaust ventilation (LEV), was more effective than natural ventilation in enclosed welding environments. Integrating air filtration with precise temperature control could reduce weld defects by up to 50%. The study provides practical recommendations for improving weld quality and promoting industrial safety.

Electrochemical impedance spectral study on the corrosion resistance of orthodontic wire made of Ni-Ti alloy immersed is artificial saliva in the presence of beer an alcoholic drink

2025-06-15

Nilavan Anitha , R. Dorothy , K. Arjunan +7 more | Zastita materijala

To regulate tooth alignment, dentists use orthodontic wires made of materials such as SS 316L and Ni-Cr alloys. These wires are exposed to corrosive environments within the oral cavity, including … To regulate tooth alignment, dentists use orthodontic wires made of materials such as SS 316L and Ni-Cr alloys. These wires are exposed to corrosive environments within the oral cavity, including artificial saliva, food items, beverages, and orally administered medications. This study investigates the corrosion resistance of Ni-Ti alloy in artificial saliva (AS), both in the absence and presence of beer—an alcoholic beverage produced by yeast fermentation of malt and flavored with hops—using polarization techniques. The results indicate that the corrosion resistance of the Ni-Ti alloy improves in the presence of beer. This is evidenced by an increase in charge transfer resistance, impedance, and phase angle, along with a decrease in double-layer capacitance when the alloy is immersed in AS containing beer. These effects are attributed to specific ingredients present in beer. The findings suggest that individuals using orthodontic wires made of Ni-Ti alloy can consume beer without concern for corrosion-related degradation of the material. Surface morphology was examined using scanning electron microscopy (SEM) and contact angle measurements.