Effect of Heat Input on Distortions and Residual Stresses Induced by Gas Tungsten Arc Welding in SS 316L to INCONEL625 Multipass Dissimilar Welded Joints

In the present study, distortion and residual stresses in the multipass welded joint were analyzed with respect to heat input. The welded joint was produced using the gas tungsten arc welding (GTAW) process with dissimilar Ni-based filler of ERNiCrMo-3. This dissimilar joint is essential in power generating nuclear and thermal plants operating at elevated temperatures. The distortion and residual stress measurements were taken using the Vernier height gauge and XRD method. To evaluate the mechanical properties, tensile testing was carried out at room temperature. The welded joint qualified the tensile test with an average value of 593 MPa. In the weld metal, a significant variation of residual stresses is measured on the top surface of the weldment along with the thickness with peak magnitude of 145 MPa to 180 MPa at the fusion zone.

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Development of New Weld Heat Input and Dilution Equations for Gas Tungsten Arc Welding: Part 1

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2013-97358 ◽

2013 ◽

Cited By ~ 2

Author(s):

Jonathan K. Tatman ◽

Steven L. McCracken ◽

Trevor G. Hicks

Keyword(s):

Heat Input ◽

Arc Welding ◽

Filler Metal ◽

Welding Process ◽

Gas Tungsten Arc Welding ◽

Power Ratio ◽

Gas Tungsten Arc ◽

Welding Part ◽

Gtaw Process ◽

Gas Tungsten

Predicting weld dilution for machine gas tungsten arc welding (GTAW) is a challenge due to the number of variables associated with the welding process. Proper heat input and power ratio controls are critical in many welding applications to control weld dilution, such as for dissimilar metal welds where low weld dilution is necessary to prevent solidification cracking or for cladding where weld dilution is minimized to maintain corrosion resistance of the clad material. This paper discusses the preliminary development and validation of improved weld dilution, heat input, and power ratio equations for the GTAW process. The new equations incorporate power added for the hot wire GTAW process, filler metal material properties, and the heat used to melt the filler metal when added to the GTAW process. The weld dilution equation was validated by comparing calculated dilution values to measured values from bead-on-plate weld trials performed on a variety of filler metals and substrates. Results of the testing and validation along with limitations of the new equations are discussed.

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Arc Characteristics and Weld Bead Microstructure of Ti-6Al-4V Titanium Alloy in Ultra-high Frequency Pulse Gas Tungsten Arc Welding (UHFP-GTAW) Process

Materials Science ◽

10.5755/j01.ms.26.4.22329 ◽

2020 ◽

Vol 26 (4) ◽

pp. 426-431

Author(s):

Wei LI ◽

Gaochong LV ◽

Qiang WANG ◽

Songtao HUANG

Keyword(s):

Titanium Alloy ◽

Fusion Zone ◽

Arc Welding ◽

Gas Tungsten Arc Welding ◽

Weld Bead ◽

Gas Tungsten Arc ◽

Arc Characteristics ◽

Arc Pressure ◽

Gtaw Process ◽

Gas Tungsten

To resolve the problem of grain coarsening occurring in the fusion zone and the heat-affected zone during conventional gas tungsten arc welding(C-GTAW) welded titanium alloy, which severely restricts the improvement of weld mechanical properties, welding experiments on Ti-6Al-4V titanium alloy by adopting ultra-high frequency pulse gas tungsten arc welding (UHFP-GTAW) technique were carried out to study arc characteristics and weld bead microstructure. Combined with image processing technique, arc shapes during welding process were observed by high-speed camera. Meanwhile the average arc pressure under various welding parameters were obtained by adopting pressure measuring equipment with high-precision. In addition, the metallographic samples of the weld cross section were prepared for observing weld bead geometry and microstructure of the fusion zone. The experimental results show that, compared with C-GTAW, UHFP-GTAW process provides larger arc energy density and higher proportion of arc core region to the whole arc area. Moreover, UHFP-GTAW process has the obviously effect on grain refinement, which can decrease the grain size of the fusion zone. The results also revealed that a significant increase of arc pressure while increasing pulse frequency of UHFP-GTAW, which could improve the depth-to-width ratio of weld beads.

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In-Situ Neutron Diffraction Study of Gas Tungsten Arc Welding of a 1018 Plain Carbon Steel

MRS Proceedings ◽

10.1557/proc-1027-d03-05 ◽

2007 ◽

Vol 1027 ◽

Author(s):

Michael Gharghouri ◽

Michael J Watson ◽

David Dye ◽

Ronald B Rogge

Keyword(s):

Neutron Diffraction ◽

Arc Welding ◽

Neutron Diffraction Study ◽

Plain Carbon Steel ◽

Gas Tungsten Arc Welding ◽

Gas Tungsten Arc ◽

Gtaw Process ◽

Gas Tungsten ◽

In Situ Neutron Diffraction

AbstractIn-situ neutron diffraction measurements of a dynamic Gas Tungsten Arc Welding (GTAW) process have been performed using a unique instrument that establishes steady-state conditions by translating and rotating a cylindrical specimen past a stationary weld torch. The fixed neutron sampling volume is at a constant location with respect to the torch as new material is brought into the fusion zone. We present maps of lattice spacing and integrated intensity as a function of location about the weld torch, which provide insight into the temperature and phase distributions around the weld.

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A Study on Residual Stresses in Gas Tungsten Arc Welding of AA5251

Materials and Manufacturing Processes ◽

10.1080/10426914.2010.481004 ◽

2010 ◽

Vol 25 (11) ◽

pp. 1242-1250 ◽

Cited By ~ 18

Author(s):

A. R. Kohandehghan ◽

S. Serajzadeh ◽

A. H. Kokabi

Keyword(s):

Residual Stresses ◽

Arc Welding ◽

Gas Tungsten Arc Welding ◽

Gas Tungsten Arc ◽

Gas Tungsten

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Effect of Weld Heat Input Modeling and the Material Hardening Model for Gas Tungsten Arc Welding Finite Element Analysi

Journal of Welding and Joining ◽

10.5781/jwj.2021.39.3.4 ◽

2021 ◽

Author(s):

Chang-Young Oh ◽

Yongjoon Kang ◽

Seung-Gun Lee ◽

Jun-Young Jeon ◽

Sung-Sik Kang

Keyword(s):

Finite Element ◽

Heat Input ◽

Arc Welding ◽

Gas Tungsten Arc Welding ◽

Hardening Model ◽

Gas Tungsten Arc ◽

Input Modeling ◽

Gas Tungsten ◽

Weld Heat

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Residual stresses in gas tungsten arc welding: a novel phase-field thermo-elastoplasticity modeling and parameter treatment framework

Computational Mechanics ◽

10.1007/s00466-021-02104-3 ◽

2021 ◽

Author(s):

Baharin Ali ◽

Yousef Heider ◽

Bernd Markert

Keyword(s):

Residual Stresses ◽

Phase Field ◽

Arc Welding ◽

Welding Process ◽

Gas Tungsten Arc Welding ◽

Fusion Welding ◽

Isotropic Hardening ◽

Melting Front ◽

Gas Tungsten Arc ◽

Gas Tungsten

AbstractThe fusion welding process of metallic components, such as using gas tungsten arc welding (GTAW), is often accompanied by detrimental deformations and residual stresses, which affect the strength and functionality of these components. In this work, a phase-field model, usually used to track the states of phase-change materials, is embedded in a thermo-elastoplastic finite element model to simulate the GTAW process and estimate the residual stresses. This embedment allows to track the moving melting front of the metallic material induced by the welding heat source and, thus, splits the domain into soft and hard solid regions with a diffusive interface between them. Additionally, temperature- and phase-field-dependent material properties are considered. The J2 plasticity model with isotropic hardening is considered. The coupled system of equations is solved in the FE package FEniCS, whereas two- and three-dimensional initial-boundary-value problems are introduced and the results are compared with reference data from the literature.

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