The magnetic properties of nonoriented (NO) electrical steel sheet are commonly improved if the texture of their products possesses "cube texture" (e.g., {100} <0vw), "goss texture" (i.e., {110}<011), and less {222} textare. Industrially "cube type" has not been obtained, but "goss texture" has been. In a greater or lesser degree, {222} texture exists. To improve "goss texture" and reduce {222} texture, the grain size of the material prior to cold rolling should be larger. When the grain size before cold rolling is larger, during primary recrystallization, "goss texture" is enriched, {222} texture is decreased, and the grain grows so easily that higher induction and lower core loss can be obtained. This does not depend on the presence of phase transformation. In case of NO steel with phase transformation, heat treatment before cold rolling has been done below the austenite transition temperature (Ac1) in order to prevent the fine grain size caused by alpha -> gamma(+alpha) ->alpha transformation. By using material that was heated over Ac1 and cooled with changing cooling rates, this study describes (a) the relationship between textures before cold rolling and the texture of the final product, and (b) the development of the magnetic properties.
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