A skilled welder determines the weld joint penetration from his/her observation of the weld pool surface during the welding process. This paper addresses the characterization of the 3D weld pool surface in gas tungsten arc welding (GTAW), i.e., extracting a set of characteristic parameters from the 3D weld pool surface to determine the backside bead width that measures the degree of weld joint ...

An innovative laser-vision-based sensing method is proposed to measure weld pool oscillation frequency in pulsed gas tungsten arc welding (GTAW-P). A low-power five-line laser pattern is projected onto the entire weld pool surface as well as its reflection is intercepted by an imaging plane and captured by a high-speed camera. By observing and analyzing the change of the captured laser images d...

The need for the control of the depth of weld penetration has been and remains of a long term interest in the automated welding process. In this study, the relationship between the depth of weld penetration and the acoustic signal acquired during the laser welding process of high strength steels is investigated. The acoustic signals are first preprocessed by the spectral subtraction noise reduc...

Titanium alloys have found increased applications in various industrial sectors. One of the critical issues in quality control is the weld penetration during welding. In the present paper, tungsten inert gas (TIG) welding of Ti-6Al-4V alloy with and without an activating flux was conducted. The effect of the activating flux on Ti alloy welding was investigated. A data acquisition system was use...

This paper develops a vision-based neuro-fuzzy system to control the weld joint penetration in Gas Tungsten Arc Welding (GTAW) of thin sheets. To this end, a camera equipped with a specially designed composite light-filter is used to observe the weld pool from the topside of the workpiece so that comparatively distinct images of the weld pool are obtained. As the Backside weld Width (BW) reflec...

Conventionally, the quality of the weld is ascertained only after the welding has been completed through the use of NDT techniques. A lot of time, material and manpower is wasted before one comes to know about the soundness of the weld. These limitations can be overcome if the weld is continuously monitored in real time for the assessment of defects using appropriate NDE sensors. This paper hig...

In this experimental work, Manganese oxide (MnO2), Zinc oxide (ZnO), Iron oxide (Fe2O3) and Magnesium chloride (MgCl2) were used as activating flux to investigate the effects for SS 304 in tungsten inert gas (TIG) welding. Ultimate tensile strength, percentage elongation, Penetration depth and width were studied of material SS 304. The experimental results indicated that the MnO2 and Fe2O3 flux...

Three-dimensional welding is investigated as a rapid prototyping technique for the production of real Inetallic parts using gas metal arc welding principles. A high speed machine vision system is used to study the correlation between droplet transfer parameters and resultant weld penetration characteristics. Experimental work is conducted to determine how droplet transfer frequency, droplet siz...

Gas tungsten arc welding is fundamental in those industries where it is important to control the weld bead shape and its metallurgical characteristics. However, compared to the other arc welding process, the shallow penetration of the TIG welding restricts its ability to weld thick structures in a single pass (~ 2 mm for stainless steels), thus its productivity is relativity low. This is why th...

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...