The weld pool is the core of the welding process where complex welding phenomena originate. Skilled welders acquire their process feedback primarily from the weld pool. Observation and measurement of the three-dimensional weld pool surface thus play a fundamental role in understanding and future control of complex welding processes. To this end, a laser line is projected onto the weld pool surf...

Evaluation of welding process such as metal inert gas welding and tungsten inert gas arc welding on tensile, bend and hardness properties of austenitic stainless steel SS347H(18Cr 10Ni 1Cb ), T22(21⁄4Cr Mo) and T91(9Cr 1Mo V) grades are studied. Tubes of 54 mm of outer diameter and 4 mm of wall thickness is used as a base material in the following combination SS347H VS T91 and T91 VS T22 is wel...

Double-Electrode Gas Metal Arc Welding, referred to as DE-GMAW, is a novel process which decouples the melting current into base metal current and bypass current by adding a bypass torch to a conventional GMAW system to establish a bypass arc. This makes it possible to increase the melting current while the base metal current still be controlled at a desired level. Experiments have been done to...

Welding is an important manufacturing process that can be automated and optimized. This paper focuses on the development of a robotic arc welding system, wherein a three-degreeof-freedom Selective Compliance Assembly Robot Arm (SCARA) is interfaced to a Gas Metal Arc Welding (GMAW) process. The entire system is composed of a robot linked to a GMAW system. Set points are derived using the desire...

Aluminum alloy welding suffers from problems such as solidification cracking and hydrogen-induced porosity, which are sufficiently severe to limit its potential applications. Because mitigated porosity incidence and solidification cracking are observed in aluminum welds using double pulsed gas metal arc welding (DP-GMAW), a comprehensive review of the mechanism is necessary, but absent from the...

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...

This paper investigates the dynamic behavior of Gas Metal Arc Welding (GMAW) process for two types of power supplies –inverter and rectifier- for short circuit transfer mode. The large ripples on the rectifier power source are able to perturb the metal transfer mode. In this experimental work some operating points in the short circuit mode have been selected using an automatic pipeline welding ...

Joints of complex phase 780 (CP-780) advanced high strength steel (AHSS) were carried out by using an ER-CuAl-A2 filler metal for the gas arc welding pulsed brazing (GMAW-P- brazing) process and ER-80S-D2 GMAW-P employing two levels heat input. The phases in weld bead HAZ analyzed, evaporation zinc means scanning electron microscopy (SEM) was also monitored. mechanical properties welded joints ...

METAL transfer describes the process of the molten metal movement from the electrode tip to the workpiece in gas metal arc welding (GMAW). A better understanding of the metal transfer process is important for improvements in the quality and productivity of welding. While several distinct modes of the metal transfer have been classified,[1] the globular and spray transfer modes have received att...