Numerical Simulation of Temperature Field and Residual Stress in Multi-Pass Welds in 2.25Cr-1Mo-0.25V Steel Plate and Comparison With Experimental Measurements

2017 ◽  
Author(s):  
Mu Qin ◽  
Guangxu Cheng ◽  
Zaoxiao Zhang ◽  
Qing Li ◽  
Jianxiao Zhang
Keyword(s):  
Residual Stress ◽  
Temperature Distribution ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Pressure Vessels ◽  
Residual Stress Distribution ◽  
Bottom Surface ◽  
Transient Temperature ◽  
Transient Temperature Distribution ◽  
Welding Processes

The 2.25Cr-1Mo-0.25V steels are widely used in the petroleum chemical industry for the manufacturing of pressure vessels. The multi-pass welding is a critical type of fabrication in hydrogenation reactor. However, very complicated residual stresses could be generated during the multi-pass welding process. The presence of residual stresses could have significant influence on the performance of welded product. In the present work, the transient temperature distribution and residual stress distribution in welding of 2.25Cr-1Mo-0.25V steel are analyzed by using numerical method. An uncoupled thermal-mechanical two-dimensional (2-D) FEM is proposed under the ABAQUS environment. The transient temperature distribution and the residual stress distribution during the welding processes are determined through the finite element method. A group of experiments by using the blind-hole method have been conducted to validate the numerical results. The results of 2-D model agree well with the experiment. The result shows that the maximum welding stress generated at heat affected zone (HAZ) both at the top and bottom surface whether to transverse stress or longitudinal stress.

Finite Element Modeling of Transient Temperature and Residual Stress Distribution Analysis in Multi-Pass Welding Process

2012 ◽  
Author(s):  
Guang-Ming Fu ◽  
Chen An ◽  
Marcelo Igor Lourenço ◽  
Meng-Lan Duan ◽  
Segen F. Estefen
Keyword(s):  
Residual Stress ◽  
Temperature Distribution ◽  
Stress Distribution ◽  
Heat Source ◽  
Welding Process ◽  
Source Model ◽  
Residual Stress Distribution ◽  
Transient Temperature ◽  
Fe Model ◽  
Transient Temperature Distribution

The residual stress and deformation due to the welding process have significant influences on the service performance of the welded deepwater platform hull. An exact prediction of transient temperature distribution is the important prerequisite to ensure the simulation accuracy of the welding residual stress and deformation fields, especially in the multi-pass welding process. Although the transient temperature distribution and residual stress distribution was studied in the past by various authors, the literature on 3D finite element (FE) simulation of multi-pass welding process is limited. In this paper, a FE model is developed to analyze the transient temperature and residual stress distribution of AH36 steel sheets in multi-pass welding process. A moving heat source model based on Goldak’s double-ellipsoidal heat flux distribution is employed for the heated plates. The addition of the volumetric heat source into the FE model and its movement along the welding pass are realized through a dedicated FORTRAN subroutine. The element birth and death technique in Abaqus/Standard is employed to simulate the weld filler variation with time in welded joints. The transient temperature calculated in the first stage is utilized as the input to the residual stress and distortion due to thermal shrinkage during the welding process and subsequent cooling. The results show good agreements between the temperature distribution and the geometry of weld pool obtained in the present work and those previously reported. Finally, a parametric study is performed to investigate the effect of welding variables, such as geometric parameters of Goldak’s heat source model, welding speed, pre-heat temperature and power input in the multi-pass welds, on the residual stress and distortion of the steel sheets.

Residual stresses in a large circular disc caused by local heating and cooling at its centre

1971 ◽  
Vol 6 (2) ◽  
pp. 89-98 ◽  
Author(s):  
T R Gurney
Keyword(s):  
Residual Stress ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Temperature Distribution ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Local Heating ◽  
Residual Stress Distribution ◽  
Element Analysis ◽  
Heating And Cooling

By means of a form of finite-element analysis and use of a theoretical, radially symmetrical, temperature distribution, the residual stresses resulting from spot heating at the centre of a large circular plate have been calculated. The investigation was concerned in particular with defining the effect of variations in material yield stress, rate of heat input, and peak temperature on the residual-stress distribution.

Theoretical prediction of residual stresses induced by cold spray with experimental validation

2019 ◽  
Vol 15 (3) ◽  
pp. 599-616 ◽  
Author(s):  
Dibakor Boruah ◽  
Xiang Zhang ◽  
Matthew Doré
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Cold Spray ◽  
Residual Stress Distribution ◽  
Thermal Mismatch ◽  
Individual Layer ◽  
Content Type ◽  
Layer Height ◽  
Proposed Model

PurposeThe purpose of this paper is to develop a simple analytical model for predicting the through-thickness distribution of residual stresses in a cold spray (CS) deposit-substrate assembly.Design/methodology/approachLayer-by-layer build-up of residual stresses induced by both the peening dominant and thermal mismatch dominant CS processes, taking into account the force and moment equilibrium requirements. The proposed model has been validated with the neutron diffraction measurements, taken from the published literature for different combinations of deposit-substrate assemblies comprising Cu, Mg, Ti, Al and Al alloys.FindingsThrough a parametric study, the influence of geometrical variables (number of layers, substrate height and individual layer height) on the through-thickness residual stress distribution and magnitude are elucidated. Both the number of deposited layers and substrate height affect residual stress magnitude, whereas the individual layer height has little effect. A good agreement has been achieved between the experimentally measured stress distributions and predictions by the proposed model.Originality/valueThe proposed model provides a more thorough explanation of residual stress development mechanisms by the CS process along with mathematical representation. Comparing to existing analytical and finite element methods, it provides a quicker estimation of the residual stress distribution and magnitude. This paper provides comparisons and contrast of the two different residual stress mechanisms: the peening dominant and the thermal mismatch dominant. The proposed model allows parametric studies of geometric variables, and can potentially contribute to CS process optimisation aiming at residual stress control.

A Further Study of Residual Stresses in Circumferential Welds

1973 ◽  
Vol 95 (4) ◽  
pp. 238-242 ◽  
Author(s):  
S. Vaidyanathan ◽  
H. Weiss ◽  
I. Finnie
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Base Metal ◽  
Filler Metal ◽  
Residual Stress Distribution ◽  
Experimental Results ◽  
Circumferential Welds ◽  
Single Pass ◽  
Full Penetration

The residual stress distribution for a circumferential weld between cylinders was obtained in a prior publication for a full penetration, single pass weld with no variation of alloy content across the weld. In the present work the approach is extended to cover a wider variety of weld conditions. It is shown that the effects of multipass welds, partial penetration welds, and welds with filler metal differing greatly in properties from the base metal can approximately be taken into account. Experimental results are presented to support the proposed method of analysis.

scholarly journals Separation of the Formation Mechanisms of Residual Stresses in LPBF 316L

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1234
Author(s):  
Alexander Ulbricht ◽  
Simon J. Altenburg ◽  
Maximilian Sprengel ◽  
Konstantin Sommer ◽  
Gunther Mohr ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Residual Stress Distribution ◽  
Formation Mechanisms ◽  
Micro Computed Tomography ◽  
Solidification Shrinkage ◽  
Stainless Steel 316L ◽  
Heat Accumulation ◽  
Cooling Rates

Rapid cooling rates and steep temperature gradients are characteristic of additively manufactured parts and important factors for the residual stress formation. This study examined the influence of heat accumulation on the distribution of residual stress in two prisms produced by Laser Powder Bed Fusion (LPBF) of austenitic stainless steel 316L. The layers of the prisms were exposed using two different border fill scan strategies: one scanned from the centre to the perimeter and the other from the perimeter to the centre. The goal was to reveal the effect of different heat inputs on samples featuring the same solidification shrinkage. Residual stress was characterised in one plane perpendicular to the building direction at the mid height using Neutron and Lab X-ray diffraction. Thermography data obtained during the build process were analysed in order to correlate the cooling rates and apparent surface temperatures with the residual stress results. Optical microscopy and micro computed tomography were used to correlate defect populations with the residual stress distribution. The two scanning strategies led to residual stress distributions that were typical for additively manufactured components: compressive stresses in the bulk and tensile stresses at the surface. However, due to the different heat accumulation, the maximum residual stress levels differed. We concluded that solidification shrinkage plays a major role in determining the shape of the residual stress distribution, while the temperature gradient mechanism appears to determine the magnitude of peak residual stresses.

scholarly journals Influence of Welding Defects on Residual Stresses: Numerical Study

2014 ◽  
Vol 996 ◽  
pp. 506-511
Author(s):  
Intissar Frih ◽  
Pierre Antoine Adragna ◽  
Guillaume Montay
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Numerical Study ◽  
Stress Gradient ◽  
Residual Stress Distribution ◽  
Welded Structure ◽  
Critical Defect ◽  
Welding Defects ◽  
Residual Stress Gradient

This paper presents a study on the application of the finite element methods to predict the influence of a defect on the residual stress distribution in a T-welded structure. A defect is introduced in a numerical model firstly without residual stress to see its impact (size and position) on the stress distribution. Secondly the most critical defect (determined previously) is simulated with a residual stress gradient. The obtained results are useful for computation stress concentration factor due to weld residual stresses.

Measurement of Residual Stresses in a Circular Ring Using the Successive Cracking Method

1996 ◽  
Vol 118 (2) ◽  
pp. 217-223 ◽  
Author(s):  
K. J. Kang ◽  
S. Y. Seol
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Circular Ring ◽  
Outer Edge ◽  
Residual Stress Distribution ◽  
Ring Specimen ◽  
Element Analysis ◽  
Theoretical Derivation ◽  
Sectioning Method

A method which we describe as the “successive cracking method” for measuring residual stresses in a circular ring is presented. In this method, the residual stresses are evaluated using a fracture mechanics approach. The strains measured at a point on the outer edge of the ring as a crack is introduced and extended from the edge are used to deduce the residual stress distribution in the uncracked ring. Finite element analysis is carried out to examine the validity of the theoretical derivation. Experiments to measure the residual stresses in a steel ring specimen are done by the successive cracking method. For comparison purposes, the experimental results using the sectioning method are presented as well. The successive cracking method is shown to be valid, simple, and effective for measuring the two-dimensional residual stress distribution in an axisymmetric member.

Residual Stress Relief in the Aluminium Alloy 7075

2017 ◽  
Vol 905 ◽  
pp. 31-39 ◽  
Author(s):  
Jeremy S. Robinson ◽  
Christopher E. Truman ◽  
Thilo Pirling ◽  
Tobias Panzner
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Neutron Diffraction ◽  
Residual Stresses ◽  
Aluminium Alloy ◽  
Stress Relief ◽  
Residual Stress Distribution ◽  
Cold Compression ◽  
Heat Treated ◽  
Minimum Residual

The residual stresses in heat treated 7075 aluminium alloy blocks have been characterised using two neutron diffraction strain scanning instruments. The influence of uniaxial cold compression (1-10%) on relieving the residual stress has been determined. Increasing the magnitude of cold compression from 1 to 10% has been shown to have a beneficial effect on the residual stress distribution by reducing the range between the maximum and minimum residual stresses. The effect of over aging 7075 on residual stress has also been characterised using neutron diffraction and this was found to reduce the residual stress by 25-40%. A relationship between {311} peaks widths and amount of cold compression was also observed.

Experimental and Numerical Analysis of the Distribution of Residual Stresses Induced by Laser Shock Peening in a 2050-T8 Aluminium Alloy

2011 ◽  
Vol 681 ◽  
pp. 296-302 ◽  
Author(s):  
Neila Hfaiedh ◽  
P. Peyre ◽  
I. Popa ◽  
Vincent Vignal ◽  
Wilfrid Seiler ◽  
...  
Keyword(s):  
Residual Stress ◽  
Stress Distribution ◽  
Residual Stresses ◽  
Aluminium Alloy ◽  
Residual Stress Distribution ◽  
Laser Shock Peening ◽  
Treatment Technique ◽  
Laser Shock ◽  
X Ray Diffraction ◽  
Shock Peening

Laser shock peening (LSP) is an innovative surface treatment technique successfully applied to improving fatigue performance of metallic material. The specific characteristic of (LSP) is the generation of a low work-hardening and a deep compressive residual stresses mechanically produced by a laser-induced shock wave propagating in the material. The aim of this study is to analyse the residual stress distribution induced by laser peening in 2050-T8 aluminium alloy experimentally by the X-ray diffraction technique (method sin2Y) and numerically, by a finite element numerical modelling. A specific focus was put on the residual stress distribution along the surface of the impacted material.

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