In this Part II, a thorough investigation of the melting of the electrode; the droplet formation, detachment, transfer and impingement onto the workpiece, and the weld-pool formation and dynamics was conducted. The transient melt-flow velocity and temperature distributions in the droplet and in the weld pool were calculated. The resulting crater in the weld pool and the weld-pool oscillation du...

Resistance spot welding process is one of the very useful and widely utilized joining processes in automobile industry due to its high working speed, high productivity, flexibility and economical cost operation. In this paper various optimization techniques like Taguchi method, Artificial neural network (ANN), Genetic algorithm (GA) etc. and their applications are discussed to get the optimum w...

Weld overlay of piping was first used as a method to repair components of simple configurations which were known to contain cracking. An adequate ultrasonic examination of these geometries can be achieved by using a few conventional search units. Currently the application of pre-emptive weld overlays as a mitigation technique and/or to improve the examination surface condition for more complex ...

This paper describes the development and evaluation of neural network-based systems for industrial welding process control and weld quality assessment. The developed systems utilize recurrent neural networks for process control and both recurrent networks and static networks for quality prediction. The first section describes a system capable of both welding process control and real-time weld q...

Presently, wrapping of the welds at the ends of stiffeners is not done to avoid the undercutting of the stiffener corners and the attendant weld repair. The fatigue performance of stiffeners with undercuts was evaluated in a factorial design fatigue experiment. Undercuts at the flange edge and filling of the stiffener cope with the fillet weld were also evaluated. The undercuts did not influenc...

An application of machine vision, incorporating neural networks, which aims to fully automate real-time radiographic inspection in welding processes is described. The current methodology adopted comprises two distinct stages the segmentation of the weld from the background content of the radiographic image, and the segmentation of suspect defect areas inside the weld region itself. In the first...

Mathematical models and associated numerical techniques have been developed to investigate the complicated transport phenomena in spot hybrid laser-MIG keyhole welding. A continuum formulation is used to handle solid phase, liquid phase, and the mushy zone during the melting and solidification processes. The volume of fluid (VOF) method is employed to handle free surfaces, and the enthalpy meth...

Evaluation of the low cycle fatigue life by the small specimen test technique (SSTT) and some other properties (metallographical structure and Vickers hardness) for the TIG (tungsten inert gas) weld of F82H IEA-heat were carried out. The TIG-weld was distinguished into seven regions with different metallographical structure and hardness, which were the base metal (BM) region (region with almost...

In fusion arc welding the final weld shape is influenced by welding parameters, mode of metal transfer, number of welding wires used and their arrangement in the contact tube, type of material to be welded, type of shielding medium and similar. In some articles, descriptions of investigations on the influence of the kind of material and the type of shielding medium used on the weld shape and si...

An improved welding electrode for producing weld metal having low amount of hydrogen therein so that hydrogen assisted cracking in weld zone is minimised. This is especially beneficial for welding high strength steel having tensile strengths of about 70000 psi or above. The reduction of slag /metal reaction temperature during welding have been found to have additional advantage of reducing the ...