Magnetization curve plotting from the magnetic domain images

An innovative image processing methodology is proposed to draw the magnetization curves of electrical steels. Our methodology enables to draw the continuous magnetization curve from a series of the distinct scanning electron microscope (SEM) images of magnetic domains. Our image processing methodology has two distinguished features. One is that the contrast of a domain image is regarded as an average of flux density. Another one is that domain motion observed in several domain images is represented by the image Helmholtz equation. Its solution generates any magnetized states of the magnetic domains. Moreover, computing averaged contrast of each image gives value of flux density on a magnetization curve. In this paper, we apply our methodology to the domain images of a grain-oriented electrical steel. This paper demonstrates the macroscopic- as well as microscopic-magnetization curves reflecting on their physical conditions.