| 摘要 |
PURPOSE:To simultaneously attain the control of the orientation be secondary crystals and the smoothing of the surface in the process of finish annealing by introducing a separation agent for annealing into primary-recrystallized sheets before finish- annealing of a silicon steel strip having a specified compsn. under a water-free condition. CONSTITUTION:A silicon steel strip constituted of, by weight, 0.8 to 4.8% Si, 0.012 to 0.050% acid-soluble Al and <=0.01% N, and the balance Fe is annealed as necessary and is thereafter subjected to cold rolling for one time or >= two times including process annealing to regulate its sheet thickness into a prescribed one. This steel sheet is subjected to primary recrystallization annealing and finish annealing to obtain the objective grain-oriented silicon steel sheet. In this method, as an element in the steel, 0.03 to 0.15wt.% Sn or Sb is added, and as the time of laminating primary- recrystallized sheets, the coating of the spacer of a separation agent for annealing is executed in a state that the water of hydration is not contained. In this way, the reaction between Al as an inhibitor constituting element and water can be prevented, and, by the addtion of Sn or Sb as a surface segregation element, the weakening of the inhibitor can be delayed, so that the product having high magnetic flux density can be obtd. |
