A superconducting electromagnetic acoustic transducer or EMAT

摘要

The EMAT apparatus comprises a conductive material and a current inducer. The conductive material is configured to generate a magnetic field, wherein the magnetic field has magnetic flux lines that are substantially fixed and the conductive material has a temperature that is equal to or less than a critical temperature at which the conductive material has substantially zero electrical resistance. The current inducer is configured to cause an electric current to flow in a test object that interacts with the magnetic field, wherein the electric current has a frequency that generates an acoustic wave in the test object.