Abstract
A new system for wear indication at coated tools was developed at Fraunhofer Institute for Surface Engineering and Thin Films. The system allows the detection of the wear status of the tool while the machines are running. It contains an indicating interlayer and a so called electronic nose as a sensor. The indicating interlayer is electrodeposited on the tool under the wear protection layer and contains micro encapsulated active substrances. As soon as the protective layer is damaged the active substances are released and detected by a sensor that triggers an audible or optical signal off.