Observation of the weld pool provides an effective path to understand and control the welding process. Observation data also attribute to the validation of numerical models, which helps researchers to analyze and evaluate the welding process. Extensive research has been conducted to provide in situ monitoring of the weld pool. The arc sensor was one of the first few sensors that was adopted for...

Predicting and controlling residual stresses are critical issues in welding engineering. With advancements in computer technology, a numerical simulation technique can predict welding residual stress. To accurately simulate temperature and stress fields, the thermal cycle obtained from the finite element model must be in coincidence with an actual heat source. This study performed a Gaussian di...

In regular arc welding, the arc heat is transferred from the surface of the workpiece to melt it. In keyhole plasma arc welding, the workpiece is melted by the plasma jet which heats the wall of the keyhole along the thickness direction. Penetration is achieved with reduced heat input. However, the plasma jet only gains its energy in the arc before reaching the keyhole. In the keyhole where no ...

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...

Sensing plays a key role in automating and controlling welding processes. Although arc light sensing has advantages over through-the-arc sensing for arc length control and seam tracking, the current technology relies on experimental data and lacks theoretical foundation. To improve measurement accuracy, this work addresses the theoretical foundation for arc light sensing. A theoretical model ha...

This paper presents the results of a study aimed at establishing the temperature distribution during the welding of magnesium alloy sheets by Pulsed Current Gas Tungsten Arc Welding (PCGTAW) and Constant Current Gas Tungsten Arc Welding (CCGTAW) processes. Pulsing of the GTAW welding current influences the dimensions and solidification rate of the fused zone, it also reduces the weld pool volum...

Arc welding is a common unit operation in the construction industry, where frequent changes in location and welding position make it more difficult to control fume exposures than in industries where fixed locations are the norm. Welders may be exposed to a variety of toxic airborne contaminants including manganese (Mn) and hexavalent chromium (CrVI). Local exhaust ventilation (LEV) is a well-kn...

background: one of the methods used for joining metals together is welding, which can be carried out using different techniques such as electric spot welding. this study evaluated the effect of electric spot welding on the load defl ection rate of stainless steel and chromium-cobalt orthodontic wires. materials and methods: in this experimental-laboratory study, load defl ection rate of 0.016 ×...

The various welding parameters such as welding speed, voltage and gas flow rate were varied on HSLA steel and the effects of these parameters on weld bead geometry such as penetration, width & height have been studied. Mathematical equations have been developed using factorial technique. And the result of various effects are shown in tables. (Numerical Values). INTRODUCTION Wide variety of stee...