Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

More rapid and efficient manufacturing of three-dimensional, transparent micro components

08.10.2012
At the 2012 glasstec international trade fair, which will take place in Düsseldorf from October 23 to 26, the Fraunhofer Institute for Laser Technology ILT is presenting a laser manufacturing technique for structuring transparent materials at the joint Fraunhofer booth 15/E25.
Thanks to this technique, it is now possible for the first time to manufacture even assembled components made of transparent materials such as glass from a single block – with micrometer accuracy. In contrast to ablative techniques, in-volume selective laser etching (ISLE) is exceptional for its efficient use of material.

Fused silica tubes with a diameter of one millimeter and a wall thickness of nine micrometers, hole arrays with bore diameters of 50 micrometers, microfluidic components for medical diagnostics with channels that are less than 10 micrometers in diameter: the components used in precision mechanics, medical engineering, and metrology are getting smaller and smaller as their complexity increases.

Illustration of the size of an ISLE-manufactured micro gear wheel.

Picture Source: Fraunhofer ILT, Aachen/Volker Lannert

Take the example of the clock- and watchmaking industry, where so-called jewel bearings have to be precisely manufactured and subsequently mounted. At present, experienced specialists manually produce and mount these micro components by means of grinding and polishing, which takes a lot of time. Moreover, ablative techniques always entail a loss of material –typically as high as 80% – which can seriously impact costs depending on the specific material.

Given the tiny scale of micro components, transparent, i.e. “colorless”, materials are not amenable to manual processing, as the craftsman cannot see them well enough. Consequently, manufacturers revert to using rubies, which in addition to their hardness also have the advantage of being a red color that is easily visible.

In-volume selective laser etching speeds up the manufacturing process and removes the need for assembly

In cooperation with the Chair for Laser Technology LLT at RWTH Aachen University, a new laser manufacturing technique was developed at Fraunhofer ILT. The technique shortens the manufacturing process for micro components made from transparent materials and reduces the amount of material and energy used. Now the experts have applied in-volume selective laser etching (ISLE) to the manufacture of composite and assembled parts. This means there is no longer any need to adjust and assemble the individual components in micromechanical systems. The exposure time for a gear wheel already mounted on a shaft and fitted inside a housing is only around 15 minutes using the ISLE technique.
The process works as follows: using ultrashort pulsed laser radiation, a transparent work piece is exposed in the volume with 3D resolution at precisely the areas where material is to be removed. The material is chemically and physically changed and therefore gets selectively etchable. In the subsequent wet-chemical etching process, the exposed material is removed, while the unexposed material is scarcely affected by the etching process. This process makes it possible to manufacture micro channels, shaped holes, structured parts, and complex, composite mechanical components and systems. The ISLE technique can also be used for sapphire and glass as well as ruby. It is reproducible and ensures that components are geometrically identical in series production, while also offering a high degree of geometric and design freedom. Particularly impressive are its ability to produce shapes with micrometer accuracy, as well as kerfs and bores with extremely large aspect ratios, thanks to the small focus volume. The ISLE technique enables a level of material and energy efficiency that is simply not possible to obtain mechanically using even the most advanced ablative processes.

Scaling the laser manufacturing technique for industrial application

The main challenge facing the researchers in Aachen now consists in developing the ISLE technique so that it can be used by the manufacturers of micro components. “We are constantly working on improving the scalability of our technique so that a transfer from the lab to industrial-scale production can take place sometime in the future,” explains Dr. Dagmar Schaefer, group manager at Fraunhofer ILT. “The ISLE technique is individually adapted to the customer’s requirements according to the specific application. The biggest challenge for us is to achieve both the required component specifications and a sufficiently rapid structuring process at the same time.”
The exposure speed is currently several hundred millimeters a second. The goal is to increase this to several meters a second. At present, exposing a mounted gear wheel with a diameter of three millimeters would take 15 minutes; the higher exposure speed would reduce this time by a factor of 10.
In the medium term, efforts will be aimed at exploiting the potential of the technique within individualized mass production. This entails improvements to the present state of development that include increasing laser power and repetition rates and the use of faster beam deflection systems . ISLE promises greater cost-effectiveness and flexibility in the production of micro components in small and large batches, as well as in the mass production of individualized components.

Further Contacts

Dr. Dagmar Schaefer
Head oft he Group In-Volume Structuring
Phone +49 241 8906-628
dagmar.schaefer@ilt.fraunhofer.de
Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany

Akad. Oberrat Dr. Ingomar Kelbassa
Acad. Director of the Chair for Laser Technology LLT at the RWTH Aachen University
Phone +49 241 8906-143
ingomar.kelbassa@ilt.fraunhofer.de
Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany

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

All articles from Trade Fair News >>>

The most recent press releases about innovation >>>

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

Im Focus: X-ray optics on a chip

Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.

In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...

Im Focus: Piggyback battery for microchips: TU Graz researchers develop new battery concept

Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.

Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...

Im Focus: UCI physicists confirm possible discovery of fifth force of nature

Light particle could be key to understanding dark matter in universe

Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...

Im Focus: Wi-fi from lasers

White light from lasers demonstrates data speeds of up to 2 GB/s

A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.

Im Focus: Every atom counts

Malignant cancer cells not only proliferate faster than most body cells. They are also more dependent on the most important cellular garbage disposal unit, the proteasome, which degrades defective proteins. Therapies for some types of cancer exploit this dependence: Patients are treated with inhibitors, which block the proteasome. The ensuing pile-up of junk overwhelms the cancer cell, ultimately killing it. Scientists have now succeeded in determining the human proteasome’s 3D structure in unprecedented detail and have deciphered the mechanism by which inhibitors block the proteasome. Their results will pave the way to develop more effective proteasome inhibitors for cancer therapy.

In order to understand how cellular machines such as the proteasome work, it is essential to determine their three-dimensional structure in detail. With its...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

A week of excellence: 22 of the world’s best computer scientists and mathematicians in Heidelberg

12.08.2016 | Event News

Towards the connected, automated and electrified automobiles: AMAA conference in Brussels

02.08.2016 | Event News

Clash of Realities 2016: 7th Conference on the Art, Technology and Theory of Digital Games

29.07.2016 | Event News

 
Latest News

New microchip demonstrates efficiency and scalable design

23.08.2016 | Information Technology

Genetic Regulation of the Thymus Function Identified

23.08.2016 | Life Sciences

Biomass turnover time in ecosystems is halved by land use

23.08.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>