Adaptive elastomer composites represent a new type of smart material, which offers a great potential for smart systems in the high-tech market. Potential applications focus on mechanical engineering, the automotive and aerospace sectors, process engineering, soft robotics, the biomedical sector and civil engineering.
The objective of the research presented is the development and realization of fiber-reinforced elastomer composites with magneto-sensitive stiffness and electro-adaptive shape, i.e. these new materials are able to change their mechanical properties when subjected to a magnetic field and to modify their shape when electrical voltage is applied.
Within the presentation, the achievements made while developing fiber-reinforced magneto-active elastomers (MAE) based on magnetorheological elastomers, i.e. elastomers filled with magnetic particles, are shown. The presence of these particles in the elastomeric matrix induces both magnetostriction and magneto-sensitive stiffening effects, when MAEs are subjected to a homogeneous magnetic field. The second approach presented involves generation of fiber-reinforced elastomer composites with integrated actuators based on shape memory alloys (SMA). By connecting SMA-based actuators to an electrical voltage, they rapidly heat up above their specific transition temperature, leading to a significant material deformation (i.e. length reduction in this case), a process that subsequently induces a deflection of the composite. Since the whole process is reversible, it is possible to actively control deformation of adaptive structures. Furthermore, through integration of SMA wires in a highly flexible elastomeric matrix, high deflection rates are achievable. Finally, these two different “smart material” approaches are combined in an adaptive fiber-reinforced elastomer composite, which unifies magneto-sensitive stiffness and electro-active deformability.
Future challenges consist in the further development of adaptive fiber-reinforced composites with thermoplastic matrix and the extension of the smart material application range, including morphing wings for compliant aircraft structures or adaptive rotor blades for wind turbines that could actively adapt their form depending on the flow velocity.