The Effects of Hot Band Annealing Temperature on the Texture of 1% an 2%Si Nonoriented Electrical Steels

Abstract

The effects of hot band annealing temperature on the texture of the 1% and 2%Si nonoriented electrical steel were investigated. Slab was hot rolled and then hot band annealed in the temperature range of 900°C~1100°C. The magnetic flux density and the core loss were improved by the hot band annealing because of the texture improvement. As the hot band annealing temperature was increased, the magnetic properties were improved. The microstructure of the hot band was composed of a recrystallized structure at the surface and a deformed structure near the middle plane. These hot bands were completely recrystallized after annealing above 1000°C. The main texture of the hot band was rotated cube and gamma-fibre. After hot band annealing, rotated cube changed to cube texture and gamma-fibre intensity gradually decreased. In the case of specimen without hot band annealing, rotated cube in the middle plane was changed to near {111}<112>texture and Goss texture in the surface to gamma fibre after final annealing. In the case of the hot band annealed at 900°C, Goss texture and cube texture were developed. After final annealing, the {111} and {112} texture was dramatically decreased as the hot band annealing temperature was increased. Although the total {100} texture intensity was not changed, Cube texture, {100}<001>, was strengthened and rotated cube texture, {100}<011>, weakened for 2% Si steel. However, 1% Si steel was opposed to 2% Si steel. The {110} texture was strengthened irrespective of hot band annealing temperature. As the hot band annealing temperature was increased, the Goss texture was strengthened, and this makes the anisotropy of the magnetic flux density bigger.