XXL Integral Forgings for Aerospace Applications

The integral design concept with the goal to reduce the number of parts is still a preferred solution for weight reduction in existing and new fuselage concepts. Integral Al- and Ti-forgings still have large benefits compared to machined parts from plate, as they provide an inherently better buy to fly ratio and have improved mechanical properties due to lower heat treatment cross sections and a tailored grain flow. Compared to carbon fiber solutions they offer a large cost advantage and can be produced in a proved supply chain and in high quantities. Their only disadvantage is the high press loads necessary to produce large Ti-forgings and large stress relived Al-forgings. To be prepared for future demands of large high strength forgings, the Otto Fuchs Aerospace Group has invested into a large 60 kt hydraulic press in Los Angeles, which will go into operations mid of 2018.

This paper will present the new capabilities of the 60 kt state of the art equipment and will give an overview of the recent projects in the field of alloy development and process simulation for XXL Al- and Ti-forgings. As modern aircraft design is widely based on the damage tolerance concept, one focus will be on fatigue crack propagation and fracture toughness properties of newly developed 7xxx and 2xxx high strength alloys for aerospace applications.