Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Flying High with VCSEL Heating

04.10.2018

Additive manufacturing processes are booming, with the rapid growth of the formnext trade fair a clear indication of this. At formnext 2018, the Fraunhofer Institute for Laser Technology ILT will be showing a new process in which the component in the powder bed is heated with laser diodes. As a result, distortion can be reduced, taller parts generated and new materials used.

In just three years, formnext has established itself as the industry meeting place to get the latest on additive manufacturing (AM) processes. With 470 exhibitors and nearly 22,000 visitors, the fair in Frankfurt is also an international leader.


Exposure at local preheating using VCSEL.

© Fraunhofer ILT, Aachen, Germany


With up to 2.5 kW, the working plane is preheated independently of the overall height.

© Fraunhofer ILT, Aachen, Germany / Volker Lannert

Located in Aachen, the Fraunhofer Institute for Laser Technology ILT has been involved in formnext right from the start. Its scientists have developed a lot of expertise in the field of additive manufacturing processes.

They work on a wide variety of AM topics, from increasing efficiency to developing system concepts and processes or even qualifying new materials. In Frankfurt, several Fraunhofer ILT experts will be present in Hall 3.0 at Booth E70.

Heating with kW power from above

As a highlight, the team of Fraunhofer ILT will be presenting a new process this year. This process – laser powder bed fusion (LPBF), also known as laser beam melting – can build parts with less thermally induced stress and less distortion than conventional process technology.

The internal stresses are caused by temperature gradients in the generated component: In the laser spot, temperatures above the melting point prevail, while the rest of the component cools rapidly. Depending on the geometry and material, this temperature gradient can even lead to cracks in the material. To avoid this, the component is usually heated from below via the substrate plate. However, that's not enough, especially with taller structures.

As part of the Digital Photonic Production DPP research campus, a funding initiative of the German Federal Ministry of Education and Research (BMBF), the experts from Fraunhofer ILT are working together with their partner Philips Photonics to develop solutions for this task. In the joint project DPP Nano, they have developed a set-up in which the component is heated from above.

For this purpose, an array of six vertical-cavity surface-emitting laser bars (VCSEL) with 400 W each is installed in the process chamber. With infrared radiation at 808 nm, this array can heat the device from the top to several hundred degrees Celsius during the building process. The bars can be controlled individually so that sequences of different patterns are possible. The process is monitored with an infrared camera.

In a concrete experiment, the Aachen engineers have constructed parts of Inconel® 718 and demonstrated significantly reduced distortion. The component was heated up to 500 °C.
The VCSEL heating reduces the thermal gradient, thus also the stresses, making it possible to produce taller parts. But even more interesting are the possibilities that arise for particularly difficult materials; soon, components made of titanium aluminides are to be produced. For this, the component will be heated to approx. 900 °C.

Such parts are commonly used, for example, in the hot gas section of turbochargers. In addition to turbomachinery, the process also opens up new prospects for other industrial sectors where thermally induced stresses in additive manufacturing processes have to be reduced.

More information will be available at the joint Fraunhofer Booth E70 in Hall 3.0 from November 13 to 16, 2018 at formnext in Frankfurt am Main. In addition, Andreas Vogelpoth will present the topic “VCSEL-Based Preheating for LPBF” at the TCT conference @ formnext on November 15, 2018 at 3.00 pm.

Further information about the Digital Photonic Production DPP research campus:
forschungscampus-dpp.de

Wissenschaftliche Ansprechpartner:

Andreas Vogelpoth M.Sc.
Group Laser Powder Bed Fusion LPBF
Telephone +49 241 8906-365
andreas.vogelpoth@ilt.fraunhofer.de

Christian Tenbrock M.Sc. M.Sc.
Group Laser Powder Bed Fusion LPBF
Telephone +49 241 8906-8350
christian.tenbrock@ilt.fraunhofer.de

Weitere Informationen:

http://www.ilt.fraunhofer.de/en
http://www.forschungscampus-dpp.de

Petra Nolis M.A. | Fraunhofer-Institut für Lasertechnik ILT

More articles from Process Engineering:

nachricht Harder 3D-printed tools – Researchers from Dresden introduce new process for hardmetal industry
11.10.2018 | Fraunhofer-Institut für Keramische Technologien und Systeme IKTS

nachricht New technology for ultra-smooth polymer films
28.06.2018 | 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: Goodbye, silicon? On the way to new electronic materials with metal-organic networks

Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz (Germany) together with scientists from Dresden, Leipzig, Sofia (Bulgaria) and Madrid (Spain) have now developed and characterized a novel, metal-organic material which displays electrical properties mimicking those of highly crystalline silicon. The material which can easily be fabricated at room temperature could serve as a replacement for expensive conventional inorganic materials used in optoelectronics.

Silicon, a so called semiconductor, is currently widely employed for the development of components such as solar cells, LEDs or computer chips. High purity...

Im Focus: Storage & Transport of highly volatile Gases made safer & cheaper by the use of “Kinetic Trapping"

Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles

Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...

Im Focus: Disrupting crystalline order to restore superfluidity

When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.

We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...

Im Focus: Micro energy harvesters for the Internet of Things

Fraunhofer IWS Dresden scientists print electronic layers with polymer ink

Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...

Im Focus: Dynamik einzelner Proteine

Neue Messmethode erlaubt es Forschenden, die Bewegung von Molekülen lange und genau zu verfolgen

Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Conference to pave the way for new therapies

17.10.2018 | Event News

Berlin5GWeek: Private industrial networks and temporary 5G connectivity islands

16.10.2018 | Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

 
Latest News

For a lower climate footprint, vegetarian diet beats local

23.10.2018 | Studies and Analyses

Long-distance travels complicate conservation of migratory birds

23.10.2018 | Earth Sciences

Enabling a plastic-free microplastic hunt: "Rocket" improves detection of very small particles

22.10.2018 | Ecology, The Environment and Conservation

VideoLinks
Science & Research
Overview of more VideoLinks >>>