Hybrid designs increase the complexity of the development process, so that compared to conventional designs, anisotropic material properties, material interfaces and other resulting parameters must be taken into account. Multi-axial loads in conjunction with anisotropic material behavior lead to a correspondingly demanding task for the stress-appropriate design. In addition, there is no known procedure and little experience for the development of such hybrid designs.

The paper shows that the use of high-strength carbon fibers in combination with titanium leads to efficient lightweight hybrid structures through graded material transitions, load-oriented functional separations and optimized load introduction areas. The systematically structured development process is characterized by the networking of virtual and physical methods. 

The authors present a methodical construction method using the example of a highly loaded tension-compression strut. At the concept level, partial solutions are synthesized from known ones, such as fiber composite loops for tensile force transmission and compression supports for compressive force transmission, supported by a numerical evaluation. The design detailing of the preferred variant is carried out in further in-depth comprehensive FE calculations. In addition, the use of shape optimization methods further increases the lightweight quality of the structure. 

At the same time, material and structural properties are determined at coupon level (e.g. titanium-CFRP interface) and partial concept validations are carried out on the basis of substructure tests. The findings obtained from these tests provide information and are used directly in concept development and detailing.