NON-DESTRUCTIVE TESTING OF FERROMAGNETIC MATERIALS

摘要

In order to be able to make a non-destructive testing of ferromagnetic test pieces like tube or bars, being surrounded by a rotating magnet having two pole shoes in such a manner that at the same time longitudinal flaws, holes transversal flaws and dimensions can be detected the magnetic field generated by the magnet is used simultaneously for the electrodynamic excitation of ultrasonics in the test piece as well as for measuring the stray flux.