PROCEDURE DETERMINING INTENSITY OF STRESS IN ARTICLES MADE OF FERROMAGNETIC MATERIALS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2000 - IPC

FIELD: nondestructive test of mechanical stress in articles used in mechanical engineering and gas industry. SUBSTANCE: magnetoelastic converter is placed on standard sample made of material of tested article to determine calibration coefficient, is oriented and is loaded in longitudinal direction in steps. Material of sample is magnetized in directions of 0, 45, 135 degrees and its output signal proportional to change of magnetization in directions perpendicular to magnetization directions is recorded after each loading step. Converter is positioned on tested article, material of article is magnetized in same directions. Output signal of converter proportional to change of magnetization in directions perpendicular to magnetization directions is recorded. Sample and article are magnetized along directions simultaneously by three magnetic fields different in frequency and equal in intensity. This intensity is found by mathematical dependence. EFFECT: increased precision for sections having local change of magnetic properties. 2 cl, 4 dwg, 1 tbl