Flexible 13kW fiber laser developed for rapid materials processing

26 Jul 2021

Partnership of Fraunhofer IWS and Israeli firms Civan Lasers and A. Kotliar Laser Welding Solutions for additive manufacturing apps.

Laser experts from Saxony and Israel are jointly testing a novel laser for industrial use at the Fraunhofer Institute for Material and Beam Technology (IWS) in Dresden, Germany. The system is based on the Coherent Beam Combining (CBC) method, which is still new for high-power lasers. The 13 kilowatt laser can generate different energy distribution patterns particularly quickly during operation and thus process even demanding materials precisely and quickly.

The IWS researchers intend to make the innovative laser technology from Israel available to companies worldwide in the near future. Within a European network project, the IWS is already investigating the beam shaping, which is accelerated by a factor of 1000, for the first time for additive manufacturing together with the laser manufacturer Civan Lasers and A. Kotliar Laser Welding Solutions.

The so-called Dynamic Beam laser from Jerusalem, Israel, has been installed at IWS. The institute is thus the first research facility worldwide to employ such a laser solution. Together, the scientists are hoping that the testing in Germany will result in new applications.

“This laser will push the limits of materials processing, for example in medical technology and aerospace,” said Dr. Andreas Wetzig, who heads the Cutting and Joining technology field at IWS. He refers to the research project ShapeAM within the European network program M-era.Net, which started in July 2021.

1000 times faster

In use is Coherent Beam Combining, in which the Dynamic Beam Laser from Civan combines tens of individual beams into a powerful, high quality beam. Through small phase shifts of the wave troughs and peaks in the partial beams, the laser can quickly generate completely different energy distribution patterns in the resulting processing laser beam.

While a classic laser releases most of its energy only in the center of the beam, the new system can generate energy patterns on the workpieces; for instance, in the form of a ring, a figure eight, or a horseshoe.

In principle, this was already possible in the past with beam-deflecting optics or fast oscillating mirrors. But even the fastest oscillating mirrors still need milliseconds to realign the energy patterns in the beam. The Dynamic Beam Laser, on the other hand, accomplishes this 1000 times faster, within microseconds. This speed makes it possible for the first time to use dynamic beam shaping for additive manufacturing of metals.

With the ShapeAM project, the aim is the additive manufacturing of titanium and aluminum alloys, such as those needed for space components, implants and lightweight components for mobility. The partners plan to use dynamic beam shaping to eliminate defects and thus achieve higher quality 3D printing results. Dr. Eyal Shekel, CEO of Civan, commented, “ShapeAM makes it possible for us to explore the benefits of dynamic beam shaping in metal additive manufacturing.”

Dr. Elena Lopez, department head of Additive Manufacturing at Fraunhofer IWS, adds: “We plan to use novel beam shapes and control frequencies that are not achievable with other methods to overcome challenges in crack-sensitive materials.”

Dynamic Beam doubles working speed

IWS says that it is “already predictable that the new laser will allow faster and more precise control of the melt pool dynamics in many additive and joining processes – and not only across the surface, but also in depth.”

The institute also expects advantages in laser cutting in terms of burr-free cuts with high edge quality – at twice the working speed compared to conventional fiber lasers.

The test phase in Dresden will show whether the new laser will also meet these expectations in practice. In any case, the quality and speed advantages that are already becoming apparent make the technology highly interesting for use in metal-working industry, medical technology and electromobility, as well as in aerospace industry.

Public presentations

• In a webinar on September 14, 2021, IWS will present the Dynamic Beam Laser to partners from industry and research who are interested in the project. It will subsequently be possible to test the use of the CBC fiber laser for their own applications.

• First findings from their test series the Fraunhofer scientists will present to a broader expert audience at the combined online event Laser Symposium/ISAM 2021 in Dresden from December 7 to 9, 2021.