A penetration process in electroslag welding is simulated using a two-dimensional smoothed particle hydrodynamics method to elucidate the heat transfer mechanism. The base metals are melted and forms orthogonal direction of weld line. From metal, molten metal flows downward, then pool below slag bath. distributions temperature increasing rates due conduction Joule heating also visualized clarif...

This paper presents a solid freeform fabrication (SFF) technique based on micro-plasma powder deposition (MPPD). The relationship between the geometric features of the deposited layers and the welding parameters is investigated. The arc length is controlled through the monitoring of the arc voltage. The result of building parts with functionally graded components by the MPPD process is shown as...

The objective of this laboratory study was to identify and measure manganese (Mn) fractions in chamber-generated welding fumes (WF) and to evaluate and compare the results from a sequential extraction procedure for Mn fractions with that of an acid digestion procedure for measurement of total, elemental Mn. To prepare Mn-containing particulate matter from representative welding processes, a wel...

The relationships between the acoustic signal and the modes of the welding pool, such as no-keyhole (melt-in), keyhole and cutting, in variable-polarity plasma arc welding are investigated. The Welch power spectral density (PSD) estimate and short-time Fourier transformation are implemented to analyse and identify the diVerent modes of the welding pool. The results show that the no-keyhole mode...

This paper presents a new deposition process for directly building cylindrical parts of the 5356 aluminium alloy with variable polarity gas tungsten arc welding (VPGTAW). The relationship between the geometric sizes of the deposited layer and the welding parameters is investigated. A machine vision sensor is used to monitor and control the arc length that is a key welding parameter in the achie...

This literature review, with 232 citations, was prepared under contract to the American Welding Society for its Safety and Health Committee. The review deals with studies of the fumes, gases radiation, and noise generated during various arc welding processes. Section 1 summarizes recent studies of occupational exposures, Section 2 contains information related to the human health effects, and Se...

Recently, the incidence of pneumoconiosis due to inhalation of welding fumes has become increasingly remarkable in Japan. Although several engineering methods such as local exhaust ventilation, push-pull ventilation and general (dilution) ventilation have been preferred for controlling airborne contaminants released from welding work, thorough reduction of the welder’s exposure to welding fumes...

The emission of dusts and gases, which are generated during tubular cored wire welding and which are hazardous to health and the environment, were studied. Tests included various kinds of tubular electrode wires used for welding steel, that is, rutile flux cored wires, basic flux cored wires, and metal cored wires for welding unalloyed, low-alloy, and high-alloy steels as well as self-shielded ...

Abstract: By using the Lyapunov second method, the robust control and robust optimal control for the gas tungsten arc welding dynamic process whose underlying continuous-time systems are subjected to structured uncertainties are discussed in time-domain. As results, some sufficient conditions of robust stability and the corresponding robust control laws are derived. All these results are design...

This paper deals with weld pool oscillation during pulsed gas tungsten arc (GTA) welding of unalloyed steel. Experiments were carried out in which the weld pool was triggered into oscillation during both the base time and the pulse time by short current peaks, superimposed on the pulsed welding current. The arc voltage was continuously measured during welding and the oscillation frequency spect...