PYROELECTROMAGNETIC METHOD OF NONDESTRUCTIVE TEST Russian patent published in 2002 - IPC

FIELD: non-destructive test of ferromagnetic metal articles, tests of pipes and equipment in oil and gas extracting industry, in aviation, mechanical engineering. SUBSTANCE: tested article is demagnetized and placed in electromagnetic field. Temperature relief is read from surface and stored. Then static magnetic field is switched on and temperature relief is read anew. Then first reading is subtracted from second reading. Defective areas are determined as areas having least difference temperature. EFFECT: enhanced speed of test, improved detection by depth and increased noise immunity. 4 dwg