For a definitive breakthrough of lightweight materials in the automotive industry, new processes for manufacturing, testing and measuring are necessary. For this, steel-aluminum hybrid welds are of great interest, since they can be used for load-adapted, and at the same time lightweight components. Within the project LaserLeichter (Laser Lighter), the Laser Zentrum Hannover e.V. (LZH) is currently developing a laser welding process for joining three-dimensional structures made of steel and aluminum in a hybrid design.
One of the challenges in welding steel with aluminum is to avoid hard and brittle intermetallic phases in the welding seam. These phases can occur easily, since iron and aluminum do not combine well. The goal of the scientists at the LZH and their partners in the project LaserLeichter, is to control the welding process as much as possible. Therefore, different measuring methods will be assessed.
Establishing control during and after the running process
For one, the engineers will be testing a spectroscopic control of the welding depth, which measures the emissions of the plasma. During the ongoing process, the composition of the plasma indicates the welding depth, and allows to adapt the laser output accordingly.
This control is already being evaluated at the LZH for flat welds, and will now be expanded to three-dimensional structures. Since the distance between the process zone and the measurement sensors inevitably changes in the course of the process, detecting the plasma emissions accurately is difficult. For optimal measurements, the spectrometer will be integrated into an innovative, scanner-based processing head.
Also, the scientists are testing a sensor made by the project partner Precitec GmbH & Co. KG, which can directly measure the depth of the keyhole (vapor capillary). Additionally, they are examining a thermal imaging process of the InfraTec GmbH, as well as a trailing nondestructive sample analysis using active thermal imaging from the inpro Innovationsgesellschaft für fortgeschrittene Produktionssysteme in der Fahrzeugindustrie mbH (inpro).
The processes developed within the project are tested directly on demonstrators for the automotive industry, for example on a car body element or a battery case.
Apart from the LZH, Precitec GmbH & Co. KG, InfraTec GmbH and inpro, the following companies are working together in the joint project „Development of a laser-based joining technology for dissimilar lightweight constructions” (LaserLeichter): Volkswagen AG, Scherdel Marienberg GmbH, MATFEM Partnerschaft Dr. Gese & Oberhofer, LUNOVU Integrated Laser Solutions GmbH, Brandenburg University of Technology, and Fraunhofer-Institut für Werkstoff- und Strahltechnik (Fraunhofer IWS). Associated partners in the project are TRUMPF Laser GmbH, ASTOR Schneidwerkzeuge GmbH, ThyssenKrupp Steel Europe AG, Bond-Laminates GmbH and Sapa Aluminium Profile.
The joint project is coordinated by the Robert Bosch GmbH, and the project management organisation is the VDI Technologiezentrum GmbH. LaserLeichter is financed by the Federal Ministry of Education and Research (BMBF).
LaserLeichter is a joint project within the association „Photonic Processes and Tools for Resource Efficient Lightweight Construction“. This association is coordinated by the LZH and financed by the BMBF.
Lena Bennefeld | Laser Zentrum Hannover e.V.
No compromises: Combining the benefits of 3D printing and casting
23.03.2018 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
Intelligent wheelchairs, predictive prostheses
20.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
24.04.2018 | Information Technology
24.04.2018 | Earth Sciences
24.04.2018 | Life Sciences