LASER WoP Talk No. 3 on March 9, 2022 11:00–12.30 CET

Photons in Production—From Science to Industrial Application

At the special show "Photons in Production", current research in the field of laser materials processing will be presented at the exhibition booth by the following cooperation partners:

  • Bayerisches Laserzentrum GmbH (blz)
  • Institute for Machine Tools and Industrial Management (iwb) of the Technical University of Munich (TUM)
  • Institute of Photonic Technologies (LPT) at Friedrich-Alexander-Universität Erlangen-Nürnberg

You can get a first insight into the topics through the webinar series “Photons in Production—From Science to Industrial Application” in advance. Topics included simulation and control of laser-based additive manufacturing, material processing using ultra short pulse lasers, and laser applications for electromobility.

Video recording LASER WoP Talk No. 3

Teaser image of YouTube video

Moderator: Andreas Wimmer

Andreas Wimmer was born 1989 in Altoetting and studied Physics in Berlin (Free University of Berlin) and Munich (Ludwig Maximilian University of Munich). Since 2018, he has been a Research Associate at the Institute for Machine Tools and Industrial Management (iwb) at Technical University of Munich (TUM) in the department Additive Manufacturing and became head of this department in 2021. His research focusses on the in-situ alloying during the Powder Bed Fusion of Metals using a Laser Beam.

Lazar Tomcic: Laser Material Processing as an Enabler for Innovations in Electromobility

Electric vehicles can significantly reduce the CO2 emissions of the mobility sector and, therefore, it is essential to make electromobility technically and economically attractive for producers and customers. Laser material processing can reduce production costs and enable new designs of energy storages. In this presentation, relevant laser processes will be discussed, which are currently being researched and can lead to significant advantages in various applications for electromobility.

About Lazar Tomcic:

Lazar Tomcic was born 1992 in Leipzig and studied Production and Automation at the Munich University of Applied Sciences and at the École d'ingénieur-e-s in Paris. Since 2018, he is a Research Associate at the Institute for Machine Tools and Industrial Management (iwb) in the Department of Laser Technology at the Technical University of Munich (TUM). His research focuses on inline quality assurance in laser beam welding of copper for power electronics applications.

Florian Kaufmann & Richard Rothfelder: Beam shaping in laser material processing and Additive Manufacturing

Conventional laser material processing regardless of whether it is welding, cutting or Additive Manufacturing, uses Gaussian beam profiles to achieve required results. This means the intensity profile in the focal plane can be described by a Gaussian function. This intensity distribution does not have to represent the optimum for the given process. By shaping the beam and therefore adapting the intensity it is possible to create a beneficial distribution for a specific application. The changed boundary conditions allow enhanced process control and stability. In this talk exemplary possible benefits for material processing and Additive Manufacturing will be discussed.

About Florian Kaufmann:

Florian Kaufmann is Research Associate and Head of Process Technology Metals at Bayerisches Laserzentrum GmbH in Erlangen. His scientific work focusses on processing highly reflective materials with high power laser beam sources in the visible and infrared wavelength range.

About Richard Rothfelder:

Richard Rothfelder is Research Associate at the Institute of Photonic Technologies (LPT) at Friedrich-Alexander-Universität Erlangen-Nürnberg. His scientific work focusses on local in-situ modification of titanium alloys using beam shaped laser profiles.

Oliver Hentschel: Two Color Pyrometer for temperature and melt pool size control in AM process

In this study, the potential of high-speed (HS) ratio pyrometers as tool for process control in Additive Manufacturing (AM) has comprehensively investigated and demonstrated with DED-LB\M. For this, the high-speed ratio pyrometer H322 from the company Sensortherm has coaxially implemented into the beam path of the laser processing head YC52 provided by Precitec. The on-axis alignment of the ratio pyrometer enables a feed direction-independent measurement of the ratio temperature within the interaction zone. The pyrometer is equipped with a typical PID—controller required for closed loop control. In closed-loop operation, the ratio temperature (controlled variable) of the process zone is continuously measured. As soon as the measuring value falls below or exceeds a target value defined in advance, the laser beam power is adapted accordingly (manipulated variable) in order to ensure constant ratio temperature and associated with this constant thermodynamic boundary conditions during the manufacturing of multi-layered specimens.

We could prove that in closed looped operation an approx. constant process zone temperature and associated with this a stable thermodynamic AM process can be achieved. The laser power control allows the generation of 3D-specimen (e.g. thin walls or cube-like solids) with outstanding dimensional accuracy. In addition to this, the control of the ratio temperature leads to a strict homogeneous microstructure and constant hardness.

Co-Authors: Dr. Helmut Kriz (Sensortherm GmbH); Adam Frédéric (Precitec KG); Christian Staudenmaier (Precitec KG)

About Oliver Hentschel:

Oliver Hentschel studied Physical Engineering and Applied Physics with focus on photonic technologies. Since October 2012 he has been working as a Research Associate at the Institute for Photonic Technologies (LPT) at Friedrich-Alexander-Universität Erlangen-Nürnberg. He is a member of the Additive Manufacturing research group and mainly deals with the process of Direct Energy Deposition (DED) using laser and metal powder. In addition, he has been working as a scientific consultant at Bayerisches Laserzentrum GmbH in Erlangen since 2020.

Daniel Wolf: Simulation-based prediction of stress-induced cracking during powder bed-based melting of metals by laser irradiation (PBF-LB/M).

During powder bed melting of metals with a laser beam (PBF-LB/M), high residual stresses occur due to local temperature differences. These residual stresses can lead to cracks during the manufacturing process. In this presentation, an approach for the simulative prediction of stress induced cracks in IN718 is presented.

About Daniel Wolf:

Daniel Wolf was born 1991 in Siegen and studied Mechanical Engineering at the Technical University of Munich (TUM). Since 2018, he is Research Associate at the Institute for Machine Tools and Industrial Management (iwb) at TUM in the department Additive Manufacturing. His research focusses the laser and metal powder based additive manufacturing and the simulation of the mechanical failure in the build up process.

Frederik Buckstegge: Optical Coherence Tomography for process control in ultrashort pulse laser processing

High Precision laser processing is a growing part in various industrial sectors such as semiconductor- and electronics manufacturing and medical component manufacturing. In order to ensure highest precision in laser processes such as cutting and micro/nanostructuring, the process in question has to be either studied in detail to yield optimal process parameters, or there has to be a method of measuring relevant parameters of quality during the process to directly control the process while it is running. Optical Coherence Tomography (OCT) has the potential to be a tool for in-line post-process measurements of relevant parameters such as ablation depth and geometry, as well as real-time measurements during the process itself. The presentation will provide a short description of the OCT principles and first experiments combining ultrashort pulse laser surface ablation with in-line OCT measurements.

About Frederik Buckstegge:

Frederik Buckstegge studied physics at RWTH Aachen University with a focus on experimental condensed matter physics, while also working as a Research Associate at Fraunhofer ILT/RWTH TOS for a time. After his graduation he started working in the system technology group of the Bayerisches Laserzentrum GmbH (blz), focusing mainly on optics design as well as short- and ultrashort pulse process design and development.