The laser beam welding of silica represents an innovative alternative to traditional oxyacetylene welding. The application of this technology allows an economic bonding of silica components, which raises the standards of joint qualities to a new level. In a research project, the Bauhaus-Universität Weimar analyzes the CO2-laser beam welding of silica elements numerically and experimentally in c...

Many reasons exist for companies to use quasicontinuous wave (QCW) fi ber lasers, including the fact that a fi ber laser combines the drilling and welding advantages of a pulsed Nd:YAG laser with the cutting capabilities of a CO2 laser. This combination of processing performance is not possible with the older technology, so in the past many companies owned both CO2 and Nd:YAG lasers to handle a...

The development and fabrication of fusion reactor components utilize different grades of stainless steel materials and different welding techniques. Major candidates are TIG welding, Laser welding and Electron beam welding and Narrow Gap TIG welding. The weld joints quality evaluation and their mechanical properties are to be analyzed for performance of these developed components. The welded jo...

There are two laser welding mechanisms, keyhole mode and conduction mode. Keyhole welding is widely used because it produces welds with high aspect ratios and narrow heat affected zones. However keyhole welding can be unstable, as the keyhole oscillates and closes intermittently. This intermittent closure causes porosity due to gas entrapment. Conduction welding, on the other hand, is more stab...

This work studied the effect of additions of carbon dioxide to argon shielding gas on the weld shape and microstructure of ST14 steel in pulsed Nd: YAG laser welding. By additions of carbon dioxide up to 15%,the weld area and depth/width ratio decreases while rising of carbon dioxide up to 25% causes increasing of weld area and depth/width ratio. It is observed that the weld metal microstructur...

The plasma electron temperature has been estimated starting from the spectroscopic analysis of the optical emission of the lasergenerated plasma plume during quite diverse stainless steel welding procedures (c.w. CO2 and pulsed Nd:YAG). Although the optical emissions present different spectral features, a discrete contribution of several iron lines can be highlighted in both types of welding. W...

Laser beam welding has wide acceptability due to least welding distortion, low labour costs and convenient operation. However, laser welding for dissimilar titanium and aluminium alloys is a new area which is having wider applications in aerospace, aircraft, automotive, electronics and other industries. The present study is concerned with welding parameters namely laser power, welding speed, fo...

Laser welding has been widely used in various industry fields. In order to further alter and broaden its applicability, a novel technology of laser welding under vacuum is introduced. The combination of high power laser and low ambient pressure provides an excellent welding performance and quality. In this paper, an overview on laser welding under vacuum is presented. It begins with a short int...

in the present study, an ultrafine grained (ufg) 304l stainless steel with the average grain size of 300 nm was produced by a combination of cold rolling and annealing. weldability of the ufg sample was studied by nd: yag laser welding under different welding conditions. taguchi experimental design was used to optimize the effect of frequency, welding time, laser current and laser pulse duratio...

Laser beam welding is becoming widely used in many industrial applications. This paper reviews recent research conducted on the performance, potential and problems of thick section butt joint laser welding. Common defects that occur in laser beam welding with high power laser welding are discussed and possible solutions proposed. Methods of welding process efficiency improvement are analyzed.