The project aims is to develop a new measurement method to track the stress transients in operation relevant components in nuclear power plants by using the electromagnetic acoustic transducers (EMATs) sensor technology. With multi-axial and thermo-mechanical fatigue tests on metastable austenitic stainless steels an evaluation basis for the application of the EMAT technology should be created. In addition, a specially designed test rig will be developed to verify the measurement tracking of fast changing stress states induced by various temperature transients.