Computational Design of Multifunctional Composites made of Shape Memory Alloys and Fiber Reinforced Plastics

Shape memory alloys (SMA) like Nickel-Titanium possess a very high mechanical energy density in relation to conventional drives. Fiber reinforced plastics (FRP) will be increasingly applied to create lightweight structures. Combining both innovative materials will evolve synergy effects. Due to functional integration of SMA sheets into a base of FRP it is possible to realize adaptive composites for resource-efficient constructions as for instance flaps or spoilers on cars. For this purpose the interaction between SMA as an actuator and FRP as a return spring need to be designed in a suitable way. The computation of such structures is complex because of its non-linear (SMA) and anisotropic (FRP) mechanical behavior. Therefore, a structural simulation model based on the finite element method was developed by means of the software ANSYS. Based on that simulation model it is possible to determine proper geometrical parameters for a composite made of SMA and FRP to perform a certain mechanism. The material properties of SMA or FRP could also be varied to investigate their influence. For exemplary components it could be shown that the stress-strain behavior is computable.