Thermomechanical Modelization of a New Active Material

Abstract

The controlled behavior of composite material (CBCM) is a thermomechanical active composite using Joule effect and heterogeneous thermal elongation properties as an actuator within composite structures. An ‘active layer’ made of carbon yarns is used as internal source of heat. To help the design of this composite a simple model based on thermomechanical and composite homogenization considerations is presented. A three-point bending test is used to compare the calculated results to experimental results. A good accordance between the relevant data (maximum of deflection and temperature on the plate) at stabilization being observed, the model is used to study the influence of some parameters. The position of the active layer, a design parameter of great importance, is particularly studied and an optimized solution is proposed. Then, the model is used for a sensitivity analysis of some design and working parameters. Finally, the results of a FEM model are compared to the previous.

Thermaly Active Structures for Shape Morphing Applications

“…When the temperature tends to be uniform, the thermal expansion of the glass reinforcements is equal and then greater than the one of the aramid layers: the whole structure bends in the opposite direction. This effect is classical for thick CBCM structure and can be solved by an appropriate position of the active layer in the thickness of the CBCM laminate [20]. In the present case, because of the use of a thin external active patch there is no other possibility.…”