Smart metal sheets by direct functional integration of piezoceramic fibers in microformed structures

Microassembly of piezoceramic fibers in micro cavities at the surface of sheet metal is a novel approach for high volume production of smart adaptronic structural metal parts. In this paper a technology, manufacturing processes and characterization results of metal sheets with an active piezo-metal substructure based on directly integrated piezoceramic fibers are described. The processes include micro-milling of cavities in sheet metal, precision grinding of piezoceramic fibers, PECVD insulating layers with high dielectric strength, microassembly and force-locked joining by forming. In experiments, measurements of the surface roughness and geometric parameters of the piezoceramic fibers and micro cavities were performed. Further, the electrical properties of the insulation coatings were measured. The sensor function of the piezo-metal substructure was proven by a mechanical excitation resulting in a proportional measured sensor signal.