Double-Electrode Gas Metal Arc Welding (DE-GMAW) is a novel welding process recently developed to increase welding productivity while maintaining the base metal heat input at a desired low level. In this paper, the DE-GMAW process was improved by replacing its non-consumable tungsten electrode with a consumable welding wire electrode resulting in a new process called consumable DE-GMAW. To unde...

This article analyzes the transient complex heat transfer and fluid flow in molten metal and arc plasma during the gas metal arc welding process. The model predicts the formation, growth, detachment, and transfer of droplets from the tip of a continuously fed electrode under the influences of several competing forces including gravity, electromagnetic force, arc pressure, plasma shear stress, a...

Welding fume contains elements that, in their pure forms, can be hazardous to worker health if inhaled or ingested. Therefore, the chemical composition of welding fume must be examined when considering fume toxicity. Various chemical analysis techniques are presented and their applicability to airborne particles is described. Knowledge of particle size is important because a given characterizat...

This paper gives a recent progress of welding process research in Japan, especially, an instance in the capability of the visualization and prediction of welding arcs, though the dynamic observations of spectral image by a high-speed digital video-camera with a monochromator and also the calculations by numerical models. The dynamic observations lead to visualizations of metal vapor behavior in...

A group of stainless steel arc welding processes was compared for emission rates of fume and hexavalent chromium, and costs per meter length of weld. The objective was to identify those with minimal emissions and also compare relative labor and consumables costs. The selection included flux-cored arc welding (FCAW), shielded-metal arc welding (SMAW), and multiple gas metal arc welding (GMAW) pr...

During arc welding, the arc heats and melts the workpiece as heat flux. When the welding current is given, the distribution and the intensity of the heat flux are determined by the length of the arc. The measurement and control of the arc length are fundamental in robotic and automated welding operations. Length of welding arc determines the distribution of the arc energy and thus the heat inpu...

A study was conducted on the arc and melting efficiency of the plasma arc, gas tungsten arc, gas metal arc, and submerged arc welding processes. The results of this work are extended to develop a quantitative method for estimating weld metal dilution in a companion paper. Arc efficiency was determined as a function of current for each process using A36 steel base metal. Melting efficiency was e...

A new generation of arc welder has recently become widely available at a price which is within reach of most amateurs and part-time mechanics, known as the MIG welder (metal-arc inert gas welder). In MIG welding the arc is ensheathed in a stream of inert gas which prevents the molten metal from oxidising. The stream of gas changes the character of the emitted radiation, and it is possible that ...

Results from a computational model of arc welding, in which the arc plasma, workpiece and electrode are treated self-consistently, are presented. It is demonstrated through three examples (the effect of shielding gas composition, metal vapour and electrode shape on the weld pool) that reliable prediction of weld pool depth and geometry requires that the arc plasma is included in the computation...