Characteristics of Titanium Interface Structures for Advanced FRP-Aluminium Compounds

Modern lightweight structures containing hybrid materials allow an improvement of the weight-specific properties. In this regard, the great potential of FRP-Al (fibre reinforced plastic - aluminium) structures is far from being exhausted. As an alternative to bulky riveted joints the development of integral joint concepts with good corrosion resistance has currently a high priority for aerospace industry. The DFG researcher group ‘Schwarz-Silber’ (FOR 1224) at the University of Bremen set itself the goal to explore and develop interface structures for advanced FRP-Al compounds. Considering textile, welding and casting techniques, novel joint concepts will be designed, dimensioned and produced within five interdisciplinary projects. Experimental and numerical investigations support the validation and enhancements of the developed solutions. Regarding the joint concept combining textile and welding techniques, basic investigations were done. This concept envisages the coupling of FRP with Al sheets by using Ti wire loops at the materials interface. It is intended to join the wire loops by textile techniques on the FRP side and on the Al side by laser beam welding. The results showed a correlation between the microstructure and the fracture behaviour of the Ti-FRP joint under static loading. Based on these results, first design principles for advanced FRP-Al compounds with Ti interface structures are derived.