Light, resource-efficient and at the same time robust - what is good for lightweight construction in the automobile industry is just as important for ship construction. Therefore, steel-aluminum joints are also used for ships. However, ships need completely different material thicknesses. The ten partners of the project LaSAAS, under the leadership of the Laser Zentrum Hannover e.V. (LZH), are dedicated to developing a robust laser welding process for the maritime manufacturing.
In times of scarce resources it is also important in the ship industry to lower fuel consumption and carbon dioxide output, in order to reduce the environmental impact. Already, components are being made using weight-reducing steel-aluminum constructions, such as ship hulls made of steel and superstructures made of aluminum.
In addition, such hybrid material constructions lower the center of gravity of the ship and thus stabilize it. At the moment, the different metals are joined using an adapter piece. This is done using explosive cladding, a complicated and cost intensive joining technology.
Joining steel directly to aluminum
The scientists and industrial partners of the joint project LaSAAS want to replace this adapter piece. For this purpose, the system manufacturers Precitec GmbH & Co. KG, Scansonic MI GmbH and TRUMPF Laser- und Systemtechnik GmbH are working together with the LZH to develop a laser processing head with a weld penetration depth control.
Using this, the LZH will develop a laser welding process under lab conditions that will later be tested in cooperation with the LASER on demand GmbH. Afterwards, the process will be transferred to actual applications with the semi-finished product manufacturers Druckguss Service Deutschland GmbH and Hilbig GmbH as well as the shipyards Fr. Lürssen Werft GmbH & Co. KG and MEYER WERFT GmbH & Co. In addition, the Fraunhofer Institute for Structural Durability and System Reliability (LBF) will examine the fatigue behavior of the seams, especially under the influence of corrosive media.
Controlling the weld penetration depth
Generally, when thermally welding steel to aluminum, brittle intermetallic phases occur, so that the seams can prematurely fail under stress. However, the weld seam characteristics can be optimized based on the mix ratio of the metals, respectively the weld penetration depth. Thus, the project partners plan on controlling the weld penetration depth by analyzing the spectral process emissions and short coherence interferometry.
If successful, the process can naturally become interesting for other branches which assemble large pieces, such as train coach or commercial vehicle construction, too.
The joint project “Laser Welding of Steel to Aluminum for Applications in Shipbuilding” (LaSAAS) is funded by the German Federal Ministry for Economics and Energy (BMWi), and supervised by the Forschungszentrum Jülich GmbH (PTJ).
Dr. Nadine Tinne | Laser Zentrum Hannover e.V.
PRESTO – Highly Dynamic Powerhouses
15.05.2017 | JULABO GmbH
Making lightweight construction suitable for series production
24.04.2017 | Laser Zentrum Hannover e.V.
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
17.08.2017 | Physics and Astronomy
17.08.2017 | Earth Sciences
17.08.2017 | Physics and Astronomy