METHOD MEASURING FERROMAGNETIC PHASE OF AUSTENITIC STEELS Russian patent published in 2001 - IPC

FIELD: non-destructive test of materials and articles. SUBSTANCE: method is used for measurement of ferromagnetic phase (α-phase) of austenitic steels during casting, in billets and articles, in welds and overlaying. Surface of article is scanned simultaneously by two ferrosonde pickups till signal of maximum value of one pickup, main or additional, is obtained and recorded. Magnetosensitive elements of main pickup are positioned in plane of neutral section of magnetizing magnet, on its opposite ends coaxially one to another and orthogonally to magnetization axis of magnet and longitudinal axis of pickup. Magnetosensitive elements of additional pickup are placed at angle with respect to magnetization axis of magnet. Elements of pickups are connected in gradiometer or field meter circuit. In absence of signal from one of pickups they change positions and are turned through angle at which scanning by additional pickup was conducted till signal across one of pickups was received. In case of equality of signals one makes conclusion on verity of signal and localization direction of ferromagnetic phase of material of article. EFFECT: enhanced authenticity of results and locality of measurement thanks to double check of one and same section of article. 2 cl