Lasers have been employed in a variety of welding applications for many years. And, as laser technology further develops and diversifies, its uses in welding continue to expand. This article provides an overview of high power lasers in keyhole welding. It then examines the characteristics and advantages of fiber laser sources for welding from Coherent | Rofin, in particular, and review a specif...

Welding with laser beams is an innovative technique, which is leads to higher penetration depth and a narrower seam compared to conventional welding techniques. One significant criterion of the quality of a junction is the penetration depth. Within this article a predictive control scheme is presented that optimises the process input laser power by taking the future welding speed into account. ...

Welds made with 304 austenitic stainless steel play an important role in high-pressure hydrogen storage systems. However, there are few investigations of the effect heat input on embrittlement (HE) tungsten inert gas (TIG) welded steel. In this study, HE TIG is investigated. It was found that increase welding input, ferrite content weld shows a tendency to first and then decrease. From perspect...

In this paper, methods of welding and sealing optically transparent materials using an ultrashort pulsed (USP) fiber laser are demonstrated which overcome the limit of small area welding of optical materials. First, the interaction of USP fiber laser radiation inside glass was studied and single line welding results with different laser parameters were investigated. Then multiline scanning was ...

A new spectral processing technique designed for application in the on-line detection and classification of arc-welding defects is presented in this paper. A noninvasive fiber sensor embedded within a TIG torch collects the plasma radiation originated during the welding process. The spectral information is then processed in two consecutive stages. A compression algorithm is first applied to the...

In the present study, a three-dimensional finite element model has been developed to simulate the temperature, stress and deformation fields in continuous wave (CW) laser micro-welding of thin stainless steel sheet. The welding deformation was experimentally evaluated using a single-mode fiber laser with a high-speed scanning system. Application of developed thermal model demonstrated that the ...

The full-scale Sector Model Project, which was initiated in 1995 as one of the Large Seven ITER R&D Projects, completed all R&D activities planned in the ITER-EDA period with the joint effort of the ITER Joint Central Team (JCT), the Japanese, the Russian Federation (RF) and the United States (US) Home Teams. The fabrication of a full-scale 18 toroidal sector, which is composed of two 9 sectors...

I. TECHNICAL PROGRESS The objective of this program was to seek improved process control and weldment reliability during laser welding of automotive aluminum alloys while retaining the high speed and accuracy of the laser beam welding process. In particular, we undertook a comprehensive experimental and theoretical research to understand the effects of various welding variables on the loss of a...

In pulsed Nd:YAG laser welding process, the material melts and solidifies consecutively by a peak high power laser beam. The solidification time in this process is very less as compared to that of conventional welding process. The mode of welding process is governed by the process parameters like laser energy, pulse duration, pulse frequency, power and welding speed. This paper aimed at to exam...