• 11.10.2021

    From 18 to 21 October 2021, the 40th ICALEO will provide a virtual overview of current advances in laser materials processing. Leading experts from research and industry will exchange information on the latest findings and trends. Thematic focuses are laser-based additive manufacturing, laser macro- and micromachining, laser beam sources, process monitoring, and processing strategies. But participants will also learn valuable news on the development of the global laser market and the relevant industries.

    General Chair Verena Wippo, Head of the Composites Group, has designed a challenging program with her co-chairs and an international program committee. As every year, ICALEO is hosted by the Laser Institute of America (LIA).

    These are the contributions from the LZH:

    Monday, 18 October 2021

    08:00 am (EDT) // 14:00 (CET)
    Welcome Remarks & Opening Plenary Session
    Verena Wippo

    10:00 am (EDT) // 16:00 (CET)
    [Session MACRO 1: CU-WELDING]
    Laser Beam-Submerged Arc Hybrid Welding of Thick Duplex Stainless Steel (Macro 104)
    Rabi Lahdo, Sarah Nothdurft, Jörg Hermsdorf, Ludger Overmeyer, Stefan Kaierle

    12:30 pm (EDT) // 18:30 (CET)
    Different Approaches to Prevent Solidification Cracking in Laser Beam Welding Stainless Steel-Copper Dissimilar Joints (Macro 202)
    Jonas Rinne, Sarah Nothdurft, Jörg Hermsdorf, Stefan Kaierle, Ludger Overmeyer

    12:30 pm (EDT) // 18:30 (CET)
    Influence of the Laser Beam Parameters in the LDNA Process on the Seam Geometry of Generatively Manufactured Structures (LAM 204)
    Tjorben Bokelmann, Marijan Tegtmeier, Marius Lammers, Stefan Kaierle, Jörg Hermsdorf


    Tuesday, 19 October 2021

    08:00 am (EDT) // 14:00 (CET)
    Laser-Induced Forward Transfer as a Potential Alternative to Pick-and-Place Technology When Assembling Semiconductor Components (MICRO 302)
    Matthias Springer, Jan Düsing, Jürgen Koch, Peter Jäschke, Stefan Kaierle, Ludger Overmeyer

    08:00 am (EDT) // 14:00 (CET)
    3D Fabrication and Characterization of Polymer-Imprinted Optics for Function-Integrated, Lightweight Optomechanical Systems (FLA 303)
    Fabian Kranert, Jana Budde, Moritz Hinkelmann, Jörg Neumann, Dietmar Kracht, Roland Lachmayer

    12:00 pm (EDT) // 18:00 (CET)
    [Session MACRO 4: NON-METAL / SURFACE]
    Automatically Controlled Laser-Based Welding Process for Repair Of CFRP Parts (Macro 401)
    Simon Hirt, Jan Erik Battmer, Verena Wippo, Peter Jaeschke, Stefan Kaierle, Ludger Overmeyer

    12:00 pm (EDT) // 18:00 (CET)
    [Session MACRO 4: NON-METAL / SURFACE]
    Surface Deoxidation of Aluminium Alloys with Ns-Pulsed Laser Radiation in XHV-Adequate Atmosphere for Laser Brazing Processes (Macro 404)
    Sarah Nothdurft, Jorg Hermsdorf, Stefan Kaierle, Witali Aman

    12:00 pm (EDT) // 18:00 (CET)
    [Session LAM 4: LARGE SCALE AM]
    Influence of the Laser Beam Control On the Dilution of In-Situ Alloying In Direct Diode Coaxial Laser Wire Additive Manufacturing (LAM 404)
    Nick Schwarz, Vurgun Sayilgan, Marius Lammers, Jörg Hermsdorf, Stefan Kaierle


    Wednesday, 20 October 2021

    08:00 am (EDT) // 14:00 (CET)
    [Session MACRO 5: SENSING]
    Eddy Current Detection of Laser-Dispersed Markers as a New Approach to Determining the Position of Load Supporting Means (Macro 502)
    Tjorben Griemsmann, Christian Hoff, Jörg Hermsdorf, Stefan Kaierle, Ludger Overmeyer

    08:00 am (EDT) // 14:00 (CET)
    Material Loss Analysis in Glass Additive Manufacturing By Laser Glass Deposition (LAM 503)
    Khodor Sleiman, Katharina Rettschlag, Peter Jäschke, Stefan Kaierle, Ludger Overmeyer


    On-Demand from 18 to 20 October

    Individualised and Controlled Laser Beam Pre-treatment Process for Adhesive Bonding of Fibre-Reinforced Plastics – Part III: Effects of Contaminants (MACRO 701)
    Hagen Dittmar, Peter Jaeschke, Stefan Kaierle, Ludger Overmeyer

    Influence of Process-Related Heat Accumulation of Laser Beam Welded 1.7035 Round Bars on Melt Pool Shape and Welding Defects (MACRO 707)
    Jan Grajczak, Sarah Nothdurft, Jörg Hermsdorf, Stefan Kaierle


  • 06.09.2021

    In the FOLAMI project, the Laser Zentrum Hannover e.V. (LZH), together with eight partners from industry and research, wants to develop a novel method for the laser beam welding of mixed joints of steel and aluminum. In this way, they want to reduce manufacturing and production costs in shipbuilding.

    To join large ship components cost-effectively and efficiently, shipyards such as Meyer Werft, which is involved in the project, use laser beam welding processes for joints of the same material. For deformable, thick-walled mixed joints of steel and aluminum, explosion welding is currently used. However, this process is complex, time-consuming, and cost-intensive, restricts the design freedom, and the resulting joint has only low strength. This mixed joint is necessary, for example, for adapters that connect aluminum ship superstructures to steel hulls.

    To produce joints that meet the requirements of shipbuilders, the project consortium plans to develop a new welding method. This is intended to create a high-strength, lap-welded joint with an undercut. To achieve this, the partners plan to use two intersecting laser beams. They also expect the approach to increase the formability of the component.

    In the sub-project "Laser beam welding of form-fit steel-aluminum mixed joints through weld penetration depth control" of the LZH, the scientists want to develop the form-fit and material-fit welding process of mixed joints and also apply the analysis of spectral process emissions. In that way, the weld penetration depth, and thus also the microstructure and the proportion of intermetallic phases shall be regulated. Thus, plate thickness jumps, material batch changes, or surface differences shall be compensated.

    Based on the results of the LZH, B.I.G., Coherent and Precitec Optronik GmbH intend to jointly develop an innovative laser processing head for welding depth-controlled laser beam welding. For the new welding method, they will both analyze the spectral process emissions and further develop the welding depth control based on short-coherence interferometry. In addition, the LZH, in cooperation with the semi-finished product manufacturers LASER on demand and Hilbig, will accompany the welding tests in an environment similar to the shipyard. During the project, the laser-welded semi-finished products will be evaluated by Lürssen Werft and Meyer Werft, among others, so that the process can be quickly implemented on an industrial scale. Parallel to the process development, Fraunhofer LBF will evaluate the fatigue strength of the joints through experimental investigations and, on this basis, derive a simulation model for estimating the (cyclic) seam properties.

    About FOLAMI

    In addition to the Laser Zentrum Hannover e.V., B.I.G. Technology Services GmbH, Coherent (Deutschland) GmbH, Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF, Hilbig GmbH, LASER on demand GmbH , Fr. Lürssen Werft GmbH & Co. KG, MEYER WERFT GmbH & Co. KG and Precitec Optronik GmbH are involved in the project „FOLAMI - Form-fit laser beam welding of the mixed joint of steel and aluminum for serviceable semi-finished products in shipbuilding". It is funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) as part of the "Maritime Research Program" under the technical supervision of Forschungszentrum Jülich GmbH (PtJ).

  • 24.08.2021

    A system that rivals conventional processes in terms of speed without any tool wear brings the laser drilling of composite materials a big step closer to application in aircraft construction.

    Composite materials such as carbon fiber reinforced plastics (CFRP) are ideal for lightweight construction. As a result, there is great interest in these materials in, for example, the aircraft and automotive construction industries. But the relatively high manufacturing and processing costs for these materials still prevent their widespread use. Automated and easy-to-use laser systems could make composites more attractive to these markets.

    Drilling high-quality holes in CFRP is a challenging process. On average, manufacturers drill 34,000 holes in the A350 fuselage section 13/14 alone during the production of an aircraft. Conventional drilling tools wear out quickly. To meet the exceptionally high quality requirements of the aviation industry, manufacturers have to change the drills frequently. But this is time-consuming and costly. If the tools are changed too late, conventional milling and drilling quickly lead to quality defects, such as delamination, high heat input, undesirable indentations on the sidewalls, and dimensional deviations.

    Would you like to find out more? You can find the full article in the online magazine phi - production research Hanover.


  • 30.07.2021

    In order to be able to examine the effect of active substances on cells more precisely, the Laser Zentrum Hannover e.V. (LZH) is working on a method to grow cells exclusively at selected sites on a cell culture surface. To this end, the LZH scientists, together with ibidi GmbH, Gräfelfing, and Ella Biotech GmbH, Fürstenfeldbruck, plan to use novel photocrosslinkers. These can bind to molecules, which in turn are able to bind to cells.

    Exposure mask selectively activates photocrosslinkers
    At first, the partners want to create a library of photocrosslinkers and the functional molecules, that will be binding sites for cells. Using localized UV radiation of wavelength 365 nm, the researchers want to activate the photocrosslinkers in certain areas. This allows them to bind to the otherwise cell-repellent surface. In doing so, they will use an exposure mask to determine the areas to which the crosslinkers, and thus the cells, are to adhere. The mask is to be generated by a digital micromirror device (DMD). This consists of many tiltable, individually controllable micromirrors. These can assume two states, allowing light to reach the surface and activate the photocrosslinkers or not.

    Aptamers bind specific cells
    In the next step, molecules are applied that bond to the locally applied photocrosslinkers. Due to three-dimensional structure of the so-called aptamers, they form specific binding sites for target cells. Depending on these binding sites, different cell types are able to bind to them. Cells can thus be arranged on the surface according to a predefined pattern. In the future, this will enable researchers to determine exactly at which site certain cells settle onto the surface. This can, for example, simplify investigations of cellular interactions or the influence of chemical substances on certain cell types.

    As part of the project, the partners want to establish the method and create a library of usable crosslinkers and aptamers. The LZH also wants to develop a portable demonstrator that combines microscopy stage and imagesetter.

    About Mako-Zell
    The joint project Mako-Zell is funded by the German Federal Ministry of Education and Research as part of the KMU-innovativ materials research funding initiative. In addition to LZH, the companies ibidi GmbH and Ella Biotech GmbH are involved.

  • 15.07.2021

    Miroslav Zabic from the Biophotonics Group, Industrial and Biomedical Optics Department, has won the Student Paper Poster Award in the "Optical Coherence Imaging Techniques and Imaging in Scattering Media" category at the European Conferences on Biomedical Optics 2021 (ECBO 2021).

    The poster "OCT Wavenumber Calibration with Simple Reference Arm Modification" Zabic et al. describes how axial resolution of optical coherence tomography (OCT) systems can be improved. For this purpose, the open-source software OCTproZ was developed by LZH together with Leibniz Universität Hannover.

  • 22.06.2021

    From June 20th to 24th, 2021, the 25th World of Photonics Congress is taking place as a virtual platform for photonic technologies. Many of the more than 2000 lectures and posters show current research and development results from the LZH.

    The conferences CLEO® / Europe-EQEC, Lasers in Manufacturing (LiM), European Conferences on Biomedical Optics (ECBO), Digital Optical Technologies and Optical Metrology cover all areas of photonics. Every registered attendee has access to all conferences.

    Overview of the LZH presentations:

    June 21st

      CLEO® / Europe – EQEC 2021
    13:30 CEST EJ-P.6
    Oral presentation
    Room 3

    Optimizing the laser diode ray tracing model for LERP system simulation based on likelihood image sampling
    E. Chatzizyrli (1,3), M. Hinkelmann (1,3), A. Afentaki (1), R. Lachmayer (1,2,3), J. Neumann (1,3), D. Kracht (1,3)
    1 LZH, 2 Leibniz Universität Hannover, 3 Cluster of Excellence PhoenixD


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    June 22nd

      CLEO® / Europe – EQEC 2021
    19:15  CEST CJ-2.4
    Oral presentation
    Room 4

    Hybrid Mode-locking in a Thulium-doped Fiber Mamyshev Osillator
    B. Schuhbauer (1), V. Adolfs (1), P. Repgen (1), M. Hinkelmann (1,2), A. Wienke (1), J. Neumann (1,2), D. Kracht (1,2)
    1 Laser Zentrum Hannover e.V., 2 Cluster of Excellence PhoenixD)

    13:30  CEST

    Room 1

    Manufacturing and characterization of frequency tripling mirrors
    S. Balendat
    Laser Zentrum Hannover e.V.

    18:45  CEST

    Invited Talk
    Room 2

    3D-Imaging and Quantification of Collagen Networks in Mammary Tumors on different Size Scales
    S. Johannsmeier
    Laser Zentrum Hannover e.V.

    10:00 CEST Oral presentation
    Room 1

    High-power joining of duplex steels using laser beam-submerged arc hybrid welding
    R. Lahdo (1), S. Nothdurft (1), J. Hermsdorf (1), P. Urbanek (2), M. Puschmann (2), F. Riedel (2), S. Kaierle (1), L. Overmeyer (1)
    1 Laser Zentrum Hannover e.V., 2 Fraunhofer IWU

    11:15  CEST Oral presentation
    Room 3

    Laser ablation of thermoplastic composite for aerospace application
    H. Dittmar, S. Hirt, V. Wippo, P. Jäschke, S. Kaierle, L. Overmeyer
    Laser Zentrum Hannover e.V.

    11:30  CEST Oral presentation
    Room 4

    Potential health risks due to emission of hazardous substances during outdoor laser cutting
    J. Walter, C. Hennigs, M. Hustedt, J. Hermsdorf, S. Kaierle
    Laser Zentrum Hannover e.V.


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    June 23rd

    10:00  CEST Oral presentation
    Room 2

    Investigation of Kovar in PBF-LB/M
    A. Abel (1), J. Pufal (1), V. Rymanov (2), C. Hoff (1), J. Hermsdorf (1), S. Kaierle (1), A. Stöhr (2,3), S. Maklouf (3), J. Lackmann (3)
    1 Laser Zentrum Hannover e.V.,  2 Microwave Photonics GmbH

    10:45  CEST

    Oral presentation
    Room 5

    Influence of laser focus shift on porosity and surface quality of additively manufactured Ti-6Al-4V
    N. Emminghaus, C. Hoff, J. Hermsdorf, S. Kaierle
    Laser Zentrum Hannover e.V.

    11:15  CEST Oral presentation
    Room 1

    Investigations on the weld seam geometry of ultrasonic assisted laser beam welded round bars in and beside antinode position
    J. Grajczak (1), C.  Nowroth (2), S. Nothdurft (1), J. Hermsdorf (1), J. Twiefel (2), J. Wallaschek (2), S. Kaierle (1)
    1 Laser Zentrum Hannover e.V., 2 Leibniz Universität Hannover

    11:15  CEST Oral presentation
    Room 4

    Molded parts with functional surfaces – how laser microstructuring can be used for low-cost mass products
    M. Steinbach, J. Koch, P. Jäschke, S. Kaierle, L. Overmeyer
    Laser Zentrum Hannover e.V.

    12:00  CEST Oral presentation
    Room 2

    Adjusting the surface roughness of WE43 components manufactured by laser-based powder bed fusion
    T. Griemsmann, N. Söhnholz, C. Hoff, J. Hermsdorf, S. Kaierle
    Laser Zentrum Hannover e.V.

    13:30  CEST Oral presentation
    Room 4

    Enhanced forming behavior of conditioning lines by inserted microstructures for the production of 3D waveguides
    Al. Wienke (1), M. Khairulamzari Hamjah (2), G.-A. Hoffmann (1), J. Koch (1), P. Jäschke (1), J. Franke (2), L. Overmeyer (1), S. Kaierle (1)
    1 Laser Zentrum Hannover e.V., 2 Friedrich-Alexander-Universität Erlangen-Nürnberg

    13:45  CEST Oral presentation
    Room 1

    Investigations on the transmissivity and scattering behavior of additively manufactured components for laser transmission welding applications
    J. Kuklik, V. Wippo, P. Jäschke, S. Kaierle, L. Overmeyer
    Laser Zentrum Hannover e.V.

    13:45  CEST Oral presentation
    Room 2

    Structure-borne acoustic process monitoring of laser metal deposition
    I. Buchbender, C. Hoff, J. Hermsdorf, V. Wesling, S. Kaierle
    Laser Zentrum Hannover e.V.

    14:15  CEST Oral presentation
    Room 2

    Process development for laser hot-wire deposition welding with high-carbon cladding material AISI 52100
    L. Budde, M. Lammers, J. Hermsdorf, S. Kaierle, L. Overmeyer
    Laser Zentrum Hannover e.V.

    15:45  CEST Oral presentation
    Room 2

    Manufacturing of fused silica volume parts by means of laser glass deposition
    K. Rettschlag (1,2), S. Stieß (1), P. Jäschke (1), S. Kaierle (1), R. Lachmayer (1,2)
    1 Laser Zentrum Hannover e.V.; 2 Leibniz Universität Hannover



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    June 24th

      CLEO® / Europe – EQEC 2021
    12:15  CEST Oral presentation
    Room 12

    Study of Third Harmonic Generation From Thin Gradient HfxAlyOz Layers
    D. Zuber (1,2), S. Kleinert (1,2), A. Tajalli (3), M. Steinecke (4), M. Jupé (2,4), L. Jensen (2,4), D. Ristau (1,2,4), U. Morgner (1,2,4)
    1 Leibniz Universität Hannover, 2 Cluster of Excellence PhoenixD, 3 Deutsches Elektronen-Synchrotron DESY, 4 Laser Zentrum Hannover e.V.

    10:30  CEST

    Oral presentation
    Room 4

    Interaction between laser radiation and antifouling coating underwater
    S. Zimbelmann (1), B. Emde (1), J. Hermsdorf (1), S. Kaierle (1), Tim Heusinger von Waldegge (2), D. Stübing (2), M. Baumann (3)
    1 Laser Zentrum Hannover e.V., 2 Fraunhofer IFAM)

    10:30  CEST Oral presentation
    Room 5

    Experimental setup for determination of absorption coefficient of laser radiation in molten metals as a function of temperature and angle
    T. Bokelmann (1), M. Lammers (1), J. Hermsdorf (1), S. Emadmostoufi (2), O. Mokrov (2), R. Sharma (2), U. Reisgen (2), S.  Kaierle (1)
    1 Laser Zentrum Hannover e.V., 2 RWTH Aachen University

    15:15  CEST Oral presentation
    Room 2

    Rotary straightening of fine wire for LMD-W applications
    S. Pamin, M. Grafe, M. Lammers, J. Hermsdorf, S. Kaierle, L. Overmeyer
    Laser Zentrum Hannover e.V.

    15:30  CEST Oral presentation
    Room 2

    Height variation in scanned hot-wire laser surfacing processes

    A. Barroi, K. Biester, L. Budde, M. Lammers, J. Hermsdorf, L. Overmeyer
    Laser Zentrum Hannover e.V.

    15:45  CEST Oral presentation
    Room 2

    Automatic changing of weld deposit for additive manufacturing of hybrid metal-glass components using direct laser deposition
    M. Lammers (1,2), K. Biester (1), N. Schwarz (1,2), J. Hermsdorf (1), S. Kaierle (1), H. Ahlers (2)
    1 Laser Zentrum Hannover e.V., 2 Hochschule Hannover)


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  • 17.05.2021

    For her student research project on coaxial laser hot-wire cladding at the Laser Zentrum Hannover e.V. (LZH), Ann-Christin Meyer has received this year's "Tailored Forming" award of the Collaborative Research Center (SFB) 1153. The award is endowed with 500 euros and goes to the best student research project, bachelor's or master's thesis.

    Prof. Dr.-Ing Bernd-Arno Behrens presented the award on behalf of the SFB board on May 10th, 2021.

    Ann-Christin Meyer's research work was on "Contribution to the production of hybrid semi-finished products by buildup welding for tailored forming" in the Machines and Controls Group of the Materials and Processes Department. She is currently working on her master's thesis there.


  • 05.05.2021

    The Laser Zentrum Hannover e.V. (LZH) has appointed Prof. Dr. Michael Kues to its Scientific Directorate. Prof. Dr. Kues will support the LZH’s Scientific Directorate with his expertise in photonic quantum technologies with immediate effect. Prof. Dr. Kues has headed the Photonic Quantum Technologies research group at Leibniz Universität Hannover as a university professor since 2019. This group is located at the Hannover Center for Optical Technologies (HOT), in which the LZH is also involved.

    Prof. Dr. Kues was Assistant Professor at Aarhus Universitet in Denmark from 2018 to 2019, Marie-Skłodowska Curie Fellow at the University of Glasgow in 2018, and previously Head of the Nonlinear integrated quantum optics group at the Institut National de la Recherche Scientifique des Centre Énergie Matériaux et Télécommunications (INRS-EMT) in Canada. He studied physics at the Westfälische Wilhelms-Universität Münster and obtained his PhD there in 2013.

    The Scientific Directorate of the LZH advises the Board of Directors on scientific and technical issues in the field of research and development and ensures the supervision of young scientists.

  • 26.04.2021

    The research building "OPTICUM - Optics University Center and Campus" of Leibniz Universität Hannover (LUH) will be built in Hannover-Marienwerder. The new optics center in the immediate vicinity of the Laser Zentrum Hannover e.V. (LZH) will house around 120 scientists from the Cluster of Excellence "PhoenixD: Photonics, Optics, and Engineering - Innovation across Disciplines". The OPTICUM will unite researchers from the disciplines of physics, mechanical engineering, electrical engineering, mathematics, computer science and chemistry. The LZH is involved in PhoenixD together with the LUH and the TU Braunschweig.  

    The Wissenschaftsrat (German Science Council) had recommended the construction of the research building "OPTICUM - Optics University Center and Campus" on April 23, 2021. The building will cost around 54 million Euros. The research building strengthens the importance of optical technologies and the optics site Hannover.

    In the Cluster of Excellence PhoenixD, scientists from the three research institutions are investigating how complex optical systems can be realized for a fraction of today's price in a short development time using modern manufacturing processes - for example 3D printing.

    More information on OPTICUM in the LUH press release.

  • 22.04.2021

    From October 18th to 21st, 2021, the 40th ICALEO in San Diego will provide an opportunity to learn about advances in laser materials processing. It will also feature the latest developments directly from the industry in laser sources, process monitoring, and processing strategies.

    Verena Wippo, Head of the Composites Group, is shaping the program of this year's ICALEO as General Chair together with the Co-Chairs and the Laser Institute of America (LIA).

    The conference will feature presentations and posters on the following topics:

    • Laser Additive Manufacturing (LAM)
    • Laser Materials Macroprocessing (MACRO)
    • Laser Materials Microprocessing (MICRO)
    • Laser Nanomanufacturing (NANO)
    • Frontiers in Laser Applications (FLA)

    Verena Wippo will welcome you at this years ICALEO.