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 CeGlaFlex project: wafer-thin, unbreakable and flexible ceramic and glass
25.04.2017 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Additive manufacturing, from macro to nano
11.04.2017 | 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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>