REAL TIME VISUALIZATION OF ALTERNATING MAGNETIC FIELDS USING 2-DIMENSIONAL INTEGRATED HALL SENSOR ARRAY
Jongwoo Jun – Youngmin Park – Jinyi Lee
A visualization method of alternating magnetic fields done in real time with a high spatial resolution is proposed in this paper. 1024 Hall sensors are arrayed every 0.78 mm intervals in a 25×25 mm2 area on a nickel-zinc ferrite wafer for measuring the magnetic field intensity. A 2.5~20 kHz alternating magnetic field could be visualized by using this AC-type magnetic camera. The inspection of surface cracks on aluminium alloy specimens using the distribution of the alternating magnetic field was done in order to verify this method.
Keywords: magnetic field, sensor array, non-destructive testing, magnetic flux leakage, sheet type induced current, crack inspection