Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Lasers put a shine on metals

10.11.2009
Jobs are in short supply, and yet some sectors have difficulty in finding suitable trainees for specialist tasks, such as polishing injection molds.

The work is time-consuming and monotonous but requires highest levels of concentration, because any blemish in the mold can render it useless. A skilled worker may often need a whole week to polish a single metal mold. Up to now it has not been possible to use machines for this dreary work because they cannot get into the curved shapes.


Metal mold for glass manufacture: the lower part of the mold has been left unprocessed, the upper part has been laser-polished. On the right, the product that can be made using a mold of this type. (© Fraunhofer ILT)

Researchers at the Fraunhofer Institute for Laser Technology ILT in Aachen have developed a way of automating the polishing work: "We do not polish the surface by hand with grinding and polishing media. Instead we use a laser," explains Dr.-Ing. Edgar Willenborg, group leader at the ILT. "The laser beam melts the surface to a depth of about 50 to 100 micrometers. Surface tension ensures that the liquid metal flows evenly and solidifies smoothly."

Like in conventional grinding and polishing, the process is repeated with increasing degrees of fineness. In the first stage the researchers melt the surface to a depth of about 100 micrometers, in further steps they gradually reduce the depth. "We can set the melting depth by means of various parameters: the laser output, the speed at which the laser beam travels along the surface and the length of the laser pulses," states Willenborg. Laser polishing does not achieve the same surface smoothness as perfect hand polishing – hand polishers can achieve a roughness Ra of 5 nanometers, the laser at present can only manage 50 nanometers – but Willenborg still sees considerable market potential for the system.

"We will concentrate on automating the medium grades: a roughness of 50 nanometers is adequate for many applications, including the molds used for making standard plastic parts." The high-end levels of smoothness will therefore remain the domain of skilled hand polishers.

The time gained by laser polishing and the cost saving achieved are enormous. Whereas a skilled polisher needs about 10 to 30 minutes for each square centimeter, the laser polishes the same area in about a minute. A prototype of the laser polishing machine developed by the scientists in cooperation with mechanical engineering firm Maschinenfabrik Arnold has already been built. Willenborg estimates that the system will be ready for industrial use in one to two years' time. At the Euromold trade show, to be held from December 2 to 5 in Frankfurt, the researchers will be presenting examples of three-dimensional surfaces polished by laser (Hall 8, Stand M114).

Edgar Willenborg | Fraunhofer-Gesellschaft
Further information:
http://www.ilt.fraunhofer.de

More articles from Process Engineering:

nachricht Etching Microstructures with Lasers
25.10.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Applying electron beams to 3-D objects
23.09.2016 | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>