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...

One of the most common methods of carbon nanotubes (CNTs) synthesis is application of an electric-arc plasma. However, the final product in the form of cathode deposit is composed of carbon nanotubes and a variety of carbon impurities. An assay of carbon nanotubes produced in arc discharge systems available on the market shows that commercial cathode deposits contain about 10% CNTs. Given 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...

In order to improve the melting efficiency of double-TIG arc, based on synchronous induction pulsed laser double-arc, coupling-enhanced discharge phenomenon between double-arcs is studied in this paper. The laser-induced double-arc quantitatively analyzed. physical characteristics coupling are high-speed camera and spectral diagnosis technology. model established discuss particle migration duri...

The DIII–D fusion science research facility employs positive-ion based neutral beam ion sources for plasma heating and current drive experiments. Ion species produced inside the arc chamber of an ion source determine the composition of the neutral beams injected into the plasma and in turn affect the energy deposition along the cross section of the plasma. Arc chamber design and operation schem...

This paper focuses on the numerical investigation of low-voltage arc plasma behaviour with the contact opening process included. A flexible experimental setup with a rotating contact is designed to support this study. Based on the magnetohydrodynamic arc model, the elongation and the commutation behaviour of the arc plasma during the contact rotation progress are simulated. Under the given cond...

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...

Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to ...

New emerging technologies using blown arc plasma sources allow elaborating finely structured coatings which find many applications fields. Among them, Suspension Plasma Spraying consists in injecting within a dc plasma jet a liquid jet containing submicron solid particles which are plasma-sprayed to form coatings. This new technology has renewed the interest devoted to the understanding and the...

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...