Glass is a versatile, popular material for a wide range of applications. Cutting the glass is key to obtaining high-quality products. In the conventional process used to cut flat glass, a small cutter wheel scores a line into the glass. Pressure is then applied to the glass along this line so that it breaks.
Unfortunately, glass splinters may come off in the process, producing defects known as micro-cracks. The glass consequently needs to be reworked by grinding and polishing, which costs time and money. Nonetheless, damages may remain in the glass that reduce its strength.
A great deal of time and money, limited design options – reason enough to develop a better, more effective process for separating glass. In a project funded by the Federal Ministry of Education and Research (BMBF), Dr. Rainer Kübler has been working with his five-strong team on a laser-induced stress separation process for flat glass that causes minimal damage. Dr. Rainer Kübler has been awarded the Joseph-von-Fraunhofer Prize 2008 for his work.
So what do the Fraunhofer scientists do that is different? Instead of scoring the glass mechanically, they do it by applying stress. “We have to heat the glass along the required separation line without damaging it,” explains Dr. Kübler. “We do it with a CO2 laser.” The second part of the secret is to shock-cool the glass by means of a cooling nozzle following right behind the laser beam, blowing cold air onto a specific area of the glass. The temperature difference creates a stress field and, in turn, a crack. Then the thermal crack introduced into the surface by this process is opened by bending the glase plate until it separates. Extensive experience and numerical simulation have helped to manage the process and particularly the crack – to produce the crack in a controlled manner and use it as a tool. “Our process has enabled us to produce extremely high-quality glass edges. And flawless, smooth edges mean firmer glass,” says Dr. Kübler. The stability of the edges determines the strength of the entire pane.
All of this opens up entirely new applications for the use of glass panes in architecture. Thanks to the flawless edges, the installed glass panes can be made thinner without sacrificing any of their reliability. And Grenzebach, the development partner, is a global player in glass production technology, providing the new process with ready access to a global market.
Press Office | alfa
Dresdner scientists print tomorrow’s world
08.02.2017 | Fraunhofer-Institut für Werkstoff- und Strahltechnik IWS
New technology for mass-production of complex molded composite components
23.01.2017 | Evonik Industries AG
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences