Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Components made from copper powder open up new opportunities

16.02.2011
Up to now it was not possible to use Selective Laser Melting (SLM) on copper alloys. Now, however, research scientists at the Fraunhofer Institute for Laser Technology ILT have solved the technical problems that prevented this by enhancing the technique. The new method opens up new possibilities, for instance in plastics processing.

Rapid Manufacturing is making triumphant progress in industrial production as it enables digitized design engineering data to be directly and quickly translated into workpieces. In this context, SLM is particularly suitable for producing metal components of complex shapes which cannot be manufactured using conventional technology or can only be produced at very high cost.


Tool insert with internal cooling channels made of Hovadur (R) K220 produced using the SLM technique. Fraunhofer Institute for Laser Technology ILT, Aachen

In the InnoSurface project, which is funded by the German Federal Ministry of Economics and Technology (BMWi), a research team at Fraunhofer ILT in Aachen has succeeded in modifying the SLM process to make it suitable for copper materials. This opens up new opportunities, for example in the manufacture of tools for plastics processing.

In SLM the workpiece is built up layer by layer on a platform from powder material. Basically, the process functions like a printer working in three dimensions. Directed by the computer-generated design data for the planned workpiece, the metal powder is deposited in layers and then melted at the required points by a laser beam. As a result, it bonds with the already produced part of the object. Material tests have shown that steel or light-metal components produced in this way exhibit the same mechanical properties as conventionally produced parts.

Owing to the high thermal conductivity of copper and copper alloys, however, it has not been possible up to now to use SLM on these materials. Although copper has a lower melting point than steel, it also exhibits lower laser light absorption and higher heat dissipation. As a result, the melting track interupts and tiny balls of molten metal form. This creates cavities and thus reduces the density of the component. »To compensate for the high heat dissipation and the low laser light absorption by the copper during the melting process, we use a 1000-watt laser instead of the 200-watt laser that is currently the norm in SLM,« explains project manager David Becker. To achieve satisfactory results, he chose a laser that produces a particularly even beam profile. Meanwhile Becker and his team modified the entire installation to prevent the high energy input from causing disruptions. For example, they changed the inert gas control system and the mechanical equipment. »Tests with the copper alloy Hovadur K220 are already showing excellent results,« Becker continues, »with workpiece density reaching almost 100 percent.« The technique is therefore ready for industrial use.

It is the high thermal conductivity of copper and its alloys that makes them suitable for many applications. Inserts of these materials in steel injection molding tools for the manufacture of plastic parts ensure rapid heat removal at critical points. SLM makes it possible to integrate conformal cooling channels in these copper inserts to carry a coolant such as water. Cycle times and warping are reduced by fast and even cooling of the entire tool.

In the near future the Aachen-based research scientists intend to go a step further and process not only copper alloys but also pure copper to make dense components. The thermal conductivity of pure copper is almost twice as high as Hovadur K220. This makes for an interesting challenge!

Contacts at Fraunhofer ILT
If you have any questions our experts will be pleased to assist:
David Becker
Rapid Manufacturing
Phone +49 241 8906-568
david.becker@ilt.fraunhofer.de
Dr. Konrad Wissenbach
Additive Manufacturing and Functional Layers
Phone +49 241 8906-147
konrad.wissenbach@ilt.fraunhofer.de
Fraunhofer Institute for Laser Technology ILT
Steinbachstrasse 15
52074 Aachen
Phone +49 241 8906-0
Fax +49 241 8906-121

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

More articles from Process Engineering:

nachricht New manufacturing process for SiC power devices opens market to more competition
14.09.2017 | North Carolina State University

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

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>