FOR 505:  High Performance Joining for Tailored Hybrids

• Subject Area: Mechanical and Industrial Engineering
• Term: from 2003 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5470189

In order to give different structural components of safety cells the optimum mechanical properties and at the same time minimum weight, for example in automobile body structures, rail vehicles or airplane fuselages, different material connections are necessary, in which the particular specific properties of the different materials can be exploited to a great extent. Concerning this, there is a high need for qualifying high performance joining technologies, in order to realise metallurgical hybrid connections of basically different materials. The demands placed on research derive in particular from problematical areas, for example extremely different melting points of the weld partners, or the generation of brittle intermetallic phases.Within the scope of the Research Unit, fundamental scientific work is being carried out to qualify high performance joining, making it possible to join basically different material combinations, referring to multi-material design. Besides high process reliability for the procedures applied, above all, the mechanical-technological properties of the connections are of interest. In view of the possibilities of subsequent processing, sufficient formability is of great importance. An application dependant energy absorbing capacity of formed tailored hybrid blanks due to unintentional deformation in case of a crash must also be taken into consideration. Furthermore, the fatigue strength of hybrid connections as well as the ageing behaviour should be examined in continuing investigations.Besides steels of different strengths, materials under examination include lightweight metal alloys based on aluminium and magnesium. Existing high performance joining technologies like laser, electron beam and arc joining, as well as friction stir welding will be modified, concerning process-technical matters, and adapted to the material-specific properties of the joining partners in such a way that metallurgical connections can be developed with qualities matching the requirements placed on subsequent treatment. The metallurgy of the fusion zone is of special importance for joining in the liquid phase. Thus, adhesion bonding methods and mechanical connecting technologies represent an excellent supplement to the above-mentioned thermal joining and are used when welding and soldering methods reach their metallurgical limitations.

• DFG Programme: Research Units

Projects

• Erarbeitung konstruktiver und fertigungstechnischer Grundlagen zur Herstellung sicherheitsrelevanter Bauteilkomponenten aus nicht artgleichen Werkstoffen mittels Kleben und mechanischer Fügeverfahren (Applicant Hahn, Ortwin )
• Erzeugung stoffschlüssiger Hybridverbindungen mit Lichtbogen-Fügeverfahren (Applicant Reisgen, Uwe )
• Herstellung umformfähiger Tailored Hybrid Blanks aus Leichtbauwerkstoffen mittels Laserstrahllöten mit Zusatzwerkstoff (Applicant Ostendorf, Andreas )
• Herstellung von Aluminium-Stahl-Mischverbindungen durch Einsatz von Laser- und/oder Plasmastrahlen (Mikrostruktur und Festigkeit) (Applicant Vollertsen, Frank )
• Non-vacuum electron beam joining of dissimilar metal combinations (Applicant Bach, Friedrich-Wilhelm )
• Sheet hydroforming of friction stir welded hybrids composed of steel and aluminium (Applicant Merklein, Marion )

• Spokesperson: Professor Dr.-Ing. Friedrich-Wilhelm Bach (†)