Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Laser Technique Shortens Welding Process for Heat-Treatable Steels

03.08.2010
The Laser Zentrum Hannover e.V. (LZH) and the Institute of Electrotechnology (ETP) at the Leibniz Universität Hannover have developed a process to inductively harden and weld multi-piece construction elements of heat-treatable steels in one step.

Heat-treatable steels are often used for highly stressed construction elements, since they show a high tensile and endurance strength resulting from the heat treatment. In order to weld heat-treatable steels, they must pass through a complex multi-step process. This enables a flawless and stress-resistant weld between both construction elements.

The LZH and the ETP have now developed a process which combines inductive hardening and laser beam welding of multi-part construction elements in one process step. The construction elements are heated to a temperature of over 900°C, the parts are laser welded and then quenched.

The so called “hot welding” immediately reduces tensions occurring during the welding process, so that the danger of cold cracks in the welding seam and a softening of the basic material are avoided.

In order to achieve this, a processing head has been conceived and constructed, which combines inductive heating, the welding process and quench hardening in one step. The processing head consists of a laser processing head, an inductor, a quench shower and a shielding gas nozzle.

In comparison to construction elements which have not been preheated, the processing head used increased the welding depth by 25%. The welding seams and the heat-affected zone show a homogenous hardness distribution. Also, martensitic structures were detected in both areas. After the welding/hardening process has been complete, it is also possible to harden the surface of the construction material using the inductor.

The hot welding process significantly shortens the processing time for heat-treatable steels, and simplifies the process run. In addition, the process simulation developed in the project can be used for an exact calculation of the process.

This research project was funded by the Stiftung Stahlanwendungsforschung, Essen, and coordinated by the Forschungsvereinigung Stahlanwendung e.V., Düsseldorf.

Contact:
Laser Zentrum Hannover e.V.
Michael Botts
Hollerithallee 8
D-30419 Hannover
Germany
Tel.: +49 511 2788-151
Fax: +49 511 2788-100
E-Mail: m.botts@lzh.de
The Laser Zentrum Hannover e.V. (LZH) carries out research and development in the field of laser technology and is supported by the Ministry of Economic Affairs, Labour and Transport of the State of Lower Saxony (Niedersächsisches Ministerium für Wirtschaft, Arbeit und Verkehr).

You can find the LZH press releases with pictures at www.laser-zentrum-hannover.de/en/ (English) under "publications/press releases"

Michael Botts | idw
Further information:
http://www.lzh.de

More articles from Process Engineering:

nachricht New technology for ultra-smooth polymer films
28.06.2018 | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP

nachricht Diamond watch components
18.06.2018 | Schweizerischer Nationalfonds SNF

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>