Magnetic domain structures of metallic glasses

A new method is shown for determinating domain structures in scanning electron microscopes by using the backscattered electrons. The detectors are a pair of semiangular semiconductor diodes, and a special signal circuit is incorporated in the scanning electron microscope to enhance the picture of the magnetic domain wall structure. The method has been applied to metallic glasses of high magnetostrictive coefficient. After quenching, the "as received" ribbons exhibit a magnetic domain structure which is characteristic of the quenching process rather than the composition of the material. In addition, the method is able to give information about the domain wall thickness and the direction of the magnetization.