Smart Semi-finished Parts for the Application in Sheet-Metal Structures

In many fields of industry, e.g. automotive industry, light-weight concepts are gaining in importance. The background is an increasing shortage of natural resources combined with increasing requirements for comfort and safety. Through the use of light-weight concepts the efficiency of automotive vehicles and the driving dynamics are improved. Because the car body has amounts to 30% of total weight, it offers high potential for weight reduction. An increasing strength of sheet metal materials allows the reduction of thickness of auto body parts. Using the same materials this reduction leads to a decrease of structural stiffness. Adaptronic devices can be used to influence the stiffness locally. Sensors and actuators, e.g. based on piezoceramics, allow the detection and the reduction of unwanted vibrations. The state of the art application of piezomodules like Macro-Fibre-Composites (MFC) is performed with significant manual work. For high-volume production a new process chain has to be used. The paper presents a method which allows the application of piezomodules on 3D-formed parts. The application takes place before the forming operation. The encapsulation of the piezomodule is performed in different ways. In addition to a double layered sheet metal-composite a local applied sheet metal or plastic film can be used. The presented method offers good protection of the piezomodule against mechanical and chemical influences like splash water and dirt on the automotive parts. The local application method leads to a significant weight reduction.