Piezo-metal-composites as smart structures

In many applications vibration and noise are unwanted, but often inevitable. For instance in the field of automotive industry a reduction of comfort for the passenger is a result. In the range of high precision machine tooling negative influences on the quality of produced parts are possible by the appearance of unwanted vibrations. Adaptronic devices can help to improve the vibration and noise behaviour of structures. Today the production of adaptronic structures consists of two process chains: on the one hand the fabrication of structural parts, which occurs in a very efficient process with a low production time. On the other hand there is the functional integration step, which normally takes place under laboratory conditions and needs a lot of production time. For creating a smart structure the assembly of the structural part with the piezo-composite-module is performed. The authors propose a new process chain with material and functional integration in one process. Therefore a laminar piezo-module is integrated between two sheet metals by using an adhesive. After joining the compound, the semi-cured adhesive allows forming with a reduced generation of tensile loads due to friction between the blank and the piezo-module. As a last step of the process chain the adhesive fully cures and allows a coupling with a high stiffness. Experimental tests are used to characterize the functionality and to examine the process limits. Numerical studies allow the evaluation of stresses and strains in the piezo-module during forming.