The complex, the first experimental version of which has already been constructed and is being tested by scientists from this world-famous space science and technology centre, involves two energy sources, a Nd-YAG-laser (a neodymium-yttrium aluminium garnet laser), which is what performs the spot weld itself, and a special light module, a powerful source of light, the spectrum of which can be altered. And, of course, there is the requisite equipment and the corresponding software, which enables automatic welding over a pre-set program.
The crux of the method indeed lies in the use of this second, light source of radiation. Its power and spectral attributes are such that it can quickly and effectively heat a weld area and its surrounding space to a temperature, if required, to over 1000 degrees. In its turn, this is a guarantee that defects that form under the welding of cold (that is specially non-heated) parts are significantly fewer, while the need for annealing ready products is eradicated altogether.
Indeed, welders have long since known that the quality of a weld-join is essentially better if the parts to be welded are well heated. Cases have even been known when large metal parts are welded even before they have cooled after smelting. But how can you heat parts sufficiently quickly and effectively if one of them is made, for example, from invar (an iron-nickel alloy), which hardly alters its dimensions when heated, and the other is made from glass? How can they be heated to high temperatures without damaging them?
To resolve this problem, Doctor of Technical Sciences Valentin Sysoev and his colleagues proposed the use of a powerful lamp where, shining the beam of this lamp on the surface to be welded, can heat the item to the required temperature. In principle, such sources of energy could be the only ones to use for welding, only the excessively large diameter of the light beam (up to 2-3mm) and certain other features mean that they cannot be used for spot welding. However, the scientists believe that using them not for welding but for heating a surface, inside which a narrow laser beam will perform the spot weld, is not only possible, but also very necessary. The fall in temperature between the point of the weld and around it will be much smoother, and this is what defines the exceptionally high quality of the weld.
If we take account of the fact that a combined approach of this kind can use weaker lasers, than those that are traditionally applied, it will transpire that this new method is not only more effective, but is also more economical as the price of lasers is proportionate to their power. So it can be hoped that in the very near future the process of laser welding of car chassis and other items of importance to us all will be better and cheaper. The guarantee for this is the very highest level of professionalism of the team of scientists on this project and the financial support provided to the scientists by the ISTC.
Andrew Vakhliaev | alfa
Seeing the quantum future... literally
16.01.2017 | University of Sydney
Airborne thermometer to measure Arctic temperatures
11.01.2017 | Moscow Institute of Physics and Technology
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...
Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.
Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
16.01.2017 | Power and Electrical Engineering
16.01.2017 | Information Technology
16.01.2017 | Power and Electrical Engineering