Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Edge-rounding and removing burrs of glass parts with laser radiation

04.10.2012
The laser polishing process developed at the Fraunhofer Institute for Laser Technology ILT has been a well known technique in metal and glass processing for several years now.
It can be used not only for polishing surfaces, but also for rounding edges and for removing burrs e.g. split lines on parts formed by injection or compression molding. At the 2012 glasstec international trade fair, which will take place in Düsseldorf from October 23 to 26, experts from Fraunhofer ILT will be explaining the process and displaying samples of glass parts whose edges were rounded with CO2 laser radiation.

The stability of glass parts can be significantly increased by rounding their edges. Laser polishing is an economical and fast technique for edge-rounding of glass parts. When, as in laser polishing, a glass edge is processed with a CO2 laser, the material at the outermost surface layer heats up due to the surface near absorption of 80 percent of the laser radiation. A temperature just below its evaporation temperature is reached in the outher surface. This greatly decreases the viscosity of the material, while surface tension reduces the surface roughness. In contrast to conventional polishing techniques, no material is removed from the surface with laser polishing.

Part made of quartz glass, laser-polished and edge-rounded.

Picture Source: Fraunhofer ILT / Volker Lannert, Aachen

In addition, the surface of the edge is polished. Subsequently, the edge surface and adjacent areas exhibit a very low level of micro-roughness. The result is not only greater stability in the edge region, but also a noticeable increase in the gloss level of the processed area.

“You can set the degree to which the edge is to be rounded and polished by means of the process temperature in the surface near layer,” explains Annika Richmann, project manager at Fraunhofer ILT. “Although parts are usually processed using a beam diameter of several millimeters, very local processing is also possible. Laser polishing can be used on virtually all types of glass, with greater process speeds obtainable for low-melting glasses.”

Bid farewell to tangible and visible burrs

The technique is also suited to removing burrs on glass and plastic injection and compression-molded parts. As in laser polishing, material is redistributed rather than removed; burrs are diminished to the point where they can no longer be seen or felt. This technique also greatly reduces the micro-roughness of the processed areas and heightens gloss.

Polishing freeform optics

Research at Fraunhofer ILT is presently focused on applying laser polishing techniques to freeform optics, where conventional polishing techniques are very slow. Lasers shorten processing times by a factor of up to 100, depending on the surface geometry to be polished. For many applications – including optical systems for illumination optics – the roughness values now obtainable are more than adequate. The challenge for the experts charged with further developing the laser polishing technique now consists in also attaining adequate roughness for imaging optics by means of further increasing shape accuracy and reducing waviness.
For further information

Dipl.-Phys. Annika Richmann
Group Polishing
Phone +49 241 8906-282
annika.richmann@ilt.fraunhofer.de

Dr. Edgar Willenborg
Head of the Group Polishing
Phone +49 241 8906-213
edgar.willenborg@ilt.fraunhofer.de

Fraunhofer Institute for Laser Technology ILT
Steinbachstr. 15, 52074 Aachen, Germany

Axel Bauer | Fraunhofer-Institut
Further information:
http://www.ilt.fraunhofer.de

More articles from Process Engineering:

nachricht Jelly with memory – predicting the leveling of com-mercial paints
15.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA

nachricht Fraunhofer researchers develop measuring system for ZF factory in Saarbrücken
21.11.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>