Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The crack as a tool

30.05.2008
We encounter glass everywhere – as window and facade glazing, coffee-table tops and shelving. A new process makes it possible to cut the brittle material cost-efficiently and opens up new applications thanks to superior edge quality.

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
Further information:
http://www.fraunhofer.de/EN/press/pi/2008/05/ResearchNews5s2008Topic2.jsp

More articles from Process Engineering:

nachricht Quick, Precise, but not Cold
17.05.2017 | Fraunhofer-Institut für Lasertechnik ILT

nachricht A laser for divers
03.05.2017 | Laser Zentrum Hannover e.V.

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>