Due to gravity, a change in the welding position will significantly affect the flow of the molten pool, thus affecting the weld bead shape. An all-position welding process of low-power pulsed ...laser-MAG (metal active gas) hybrid welding was proposed to improve the welding efficiency and quality of all-position welding. This paper used the response surface method (RSM) to develop the weld bead geometry mathematical model. The analysis of variance confirmed the significance and accuracy of the model. The results show that the models can accurately predict the weld geometry, percentage errors for any models are less than 8.1%. Then, the effects of welding parameters and welding position on weld width, weld reinforcement, and weld penetration were analyzed. Finally, the optimal welding parameters at five positions of 0°, 45°, 90°, 135°, and 180° were obtained by numerical optimization with RSM. The study results can provide a reference for applying laser-MAG hybrid welding in all-position welding.
In this study all-position automatic tungsten inert gas (TIG) welding was exploited to enhance quality and efficiency in the welding of copper-nickel alloy pipes. The mathematical models of ...all-position automatic TIG weld bead shapes were conducted by the response surface method (RSM) on the foundation of central composition design (CCD). The statistical models were verified for their significance and adequacy by analysis of variance (ANOVA). In addition, the influences of welding peak current, welding velocity, welding duty ratio, and welding position on weld bead geometry were investigated. Finally, optimal welding parameters at the welding positions of 0° to 180° were determined by using RSM.
This book deals with metal processing and its numerical modelling and simulation. In total, 21 papers from different distinguished authors have been compiled in this area. Various processes are ...addressed, including solidification, TIG welding, additive manufacturing, hot and cold rolling, deep drawing, pipe deformation, and galvanizing. Material models are developed at different length scales from atomistic simulation to finite element analysis in order to describe the evolution and behavior of materials during thermal and thermomechanical treatment. Materials under consideration are carbon, Q&T, DP, and stainless steels; ductile iron; and aluminum, nickel-based, and titanium alloys. The developed models and simulations shall help to predict structure evolution, damage, and service behavior of advanced materials.
Welding parameters for pipe joint friction stir welding (FSW) have been identified based on L-9 orthogonal arrays used in the Taguchi Method. Different welding parameters, such as rotation speed, ...travel speed and axial force, have been used to produce several quality friction stir welded AA6063 pipe butt joints. The reliability of products obtained in the FSW process can be improved through the identification of the optimum combination of welding parameters. Weld quality was evaluated based on its tensile strength and residual stress profiles. The S/N analysis and Analysis of Variance (ANOVA) have been used to determine significant welding parameters that affect weld quality. Maximum tensile strength with acceptable residual stress was obtained at the optimum welding parameters of 1300 rpm, 5 mm/s and axial force between 5 and 6 kN. The goal of this study was to optimize welding parameters for high tensile strength and low residual stress.
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