Laserinduzierte Schallemissionsanalyse - ein innovatives Oberflächenprüfverfahren

Short laser pulses focussed at the materials surface are used to simulate thermal shocks. It is well known that ultrasound can be generated in thes way. If the laser pulse energy is high enough additionally irreversible processes (phase transitions, growning of micro cracks) appear. An equipment is presented which is able to detect acoustic emissions to be initiated according to these effects. Testing of laser resistent dielectric layers was an application of the method.