L. Novotný¹, M. Tsunori²

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.3&4, pp. 253-264, 2011, DOI:10.32604/cmes.2011.082.253

Abstract The welding simulation is carried out by an uncoupled thermal and mechanical analysis or by a coupled thermo-mechanical analysis. For weld-induced distortion and residual stress simulation, nonlinear mechanical analysis is required. Nonlinearities are caused by both nonlinear behaviour of the material and geometrical nonlinearity. Usually, the element birth technique is used to incorporate the filler material in the model. The ideal straight geometry may be altered by imperfections to enable buckling behaviour. Real component shapes contain various imperfections (e.g. geometrical, material). The finite element mesh may contain geometrical imperfections too. When a simple weld model is used, the mode of… More >

Rui Wang¹, Jianxun Zhang¹, Hisashi Serizawa², Hidekazu Murakawa²

CMES-Computer Modeling in Engineering & Sciences, Vol.44, No.1, pp. 97-114, 2009, DOI:10.3970/cmes.2009.044.097

Abstract In this paper, the inherent deformation of fillet welded thin plate T-joints is studied. The prediction procedure of inherent deformation consists of three parts: part one, a three dimensional (3D) thermo-elastic-plastic analysis using an in house finite element (FE) code of interactive substructure method (ISM) is utilized to obtain the welding distortions; part two, corresponding experiments are carried out to verify the computational results of ISM; part three, using the verified computational results, the inverse analysis is utilized to evaluate the welding inherent deformation. Based on the results in this study, an inherent deformations database of fillet welded thin plate… More >

Tae-Jong Yun¹, Won-Bin Oh¹, Bo-Ram Lee¹, Joon-Sik Son², Ill-soo Kim^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.1, pp. 1-14, 2019, DOI:10.32604/fdmp.2019.04759

Abstract Detection of weld defects using real-time monitoring and controlling algorithm is of the significant task in manufacturing industries due to the increased production and liability costs that result when weld defects are not identified early in the production cycle. Monitoring and controlling for robotic arc welding process employed should be reliable, flexible and cost-effective in non-clean, high-volume production environments. Also, the robotic welding system has been utilized a complex jigging and mechanical devices to move the workpiece which related to the stationary welding head for getting higher efficiency and lower costs. To develop the fully robotic welding system, people make… More >

Adeline Tchikango Siagam¹, Gunther Brenner¹, Peter Giese², Volker Wesling²

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.2, pp. 77-84, 2008, DOI:10.3970/fdmp.2008.004.077

Abstract The PTA (''Plasma-Transferred-Arc'') is a widespread variant of plasma powder processes to manufacture coatings against corrosion or abrasion. For the optimization of this technique, an explanation of the processes which lead to a maximal deposition performance (i.e. maximal quantity of powder converted per time) is required. Especially the gas and particle flow in the region between the burner nozzle and the work piece is of interest. In the present study, flow simulations (Computational Fluid Dynamics, CFD) have been done in order to investigate the determining factors for the dimensioning of the processes. Additionally, velocity measurements have been obtained with PIV… More >

Gustav Amberg¹, Junichiro Shiomi²

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.1, pp. 81-96, 2005, DOI:10.3970/fdmp.2005.001.081

Abstract A few issues in materials science are reviewed with regard to the importance of fluid flows. The effect of convection on generic solidification problems is discussed. One relevant class of flows in melts is those driven by surface tension gradients. In welding this thermo- or solutocapillary flow will determine the penetration depth, and will depend very sensitively on the composition of the material, through the dependence of surface tension on temperature, presence of surfactants, etc. In crystal growth the convective motion in the melt may cause instabilities that are often undesired in practical processes. The unsteady flow structure can cause… More >

¹Poh-Sang Lam², Jwo Pan³

CMC-Computers, Materials & Continua, Vol.46, No.1, pp. 1-16, 2015, DOI:10.3970/cmc.2015.046.001

Abstract A full range of stress intensity factor solutions for a kinked crack with finite length is developed as a function of weld width and the sheet thickness. When used with the main crack solutions (global stress intensity factors) in terms of the applied load and the specimen geometric parameters, the fatigue lives of the kinked crack can be estimated for the laser-welded lap-shear specimens. The predicted curve for the load range-fatigue life passes through the cluster of experimental data and is in good agreement. A classical solution associated with an infinitesimal kink is also employed. However, its life prediction tends… More >

M.R. Khoshravan¹ and M.A. Setoodeh¹

CMC-Computers, Materials & Continua, Vol.16, No.3, pp. 195-228, 2010, DOI:10.3970/cmc.2010.016.195

Abstract The use of welding to permanently join plates is common in industry due to its high efficiency. But welding creates thermal stresses, which can lead to residual stresses and physical distortion. This phenomenon directly influences the buckling stiffness of the welded structure. The welding distortion not only makes difficult the erection of the project, but also influences the final quality and cost of production. In this research, the thermo-elastic-plastic conditions were simulated by a three-dimensional (3D) finite element model (FE). Mechanical and thermal properties of the material were applied to the model, leading to eigenvalue analysis of the thermal and… More >