Magnetic particle inspection magnetizes workpieces made of magnetic materials such as steel and the like, utilizes the characteristic that the defective parts can absorb magnetic particles, and displays surface defects and near-surface defects of the detected objects according to the distribution of the magnetic particles. The flaw detection method is characterized by simplicity and intuitive display.
Magnetic particle inspection is the same as magnetic inspection using Hall element, magnetic sensitive semiconductor element, magnetic tape recording and coil induced electromotive force.