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Title: Method for manufacturing single-oriented electrical steel sheets comprising antimony and having a high magnetic induction
Claims: What is claimed is: 1. A method of manufacturing single-oriented electrical steel sheet comprising: a. hot rolling a silicon steel raw material consisting essentially of less than 0.06% of carbon, less than 4% of silicon, 0.012 to 0.045% of antimony aand 0.008 to 0.10% of at least one member of a group selected from selenium, sulphur and tellurium, and 0.02 to 0.2% of manganese, to an intermediate gauge of about 2-5mm; b. effecting at least one cold rolling at a reduction rate of 40-85% so as to form a cold rolled steel sheet having final gauge; c. decarburization annealing said sheet in a wet hydrogen atmosphere at 750.degree.-850.degree.C to minimize the amount of carbon in said sheet subsequently; d. subjecting the sheet to a secondary recrystallization annealing at a temperature of 800.degree.-920.degree.C for 10 to 120 hours selected so as to grow the crystal grains having (110) (001) orientation; and thereafter; e. subjecting the sheet to a purification annealing at a temperature greater than 1,000.degree.C and fluctuating in direct proportion to the silicon content so as to remove S and Se, whereby the iron loss of the final product is decreased. 2. A method of manufacturing single-oriented electrical steel sheet comprising: a. hot rolling a silicon steel raw material consisting essentially of less than 0.06% of carbon, less than 4% of silicon, 0.005 to 0.2% of antimony and 0.008 to 0.10% of at least one member of a group selected from selenium, sulphur and tellurium, and 0.02 to 0.2% of manganese, to an intermediate gauge of about 2-5mm; b. effecting at least one cold rolling at a reduction rate of 40 to 85% so as to form a cold rolled steel sheet having its final gauge; c. decarburization annealing of 750.degree.-850.degree. said sheet in a wet hydrogen atmosphere to minimize the carbon subsequently; d. subjecting the sheet to a secondary recrystallization annealing at a temperature of 800.degree. to 920.degree.C for 10 to 120 hours selected so as to grow the crystal grains having (110) (001) orientation; and thereafter; e. subjecting the sheet to a purification annealing at a temperature greater than 1,000.degree.C and fluctuating in direct proportion to the silicon content so as to remove S and Se, whereby the iron loss of the final product is decreased. 3. A method of manufacturing single-oriented steel sheet as defined in claim 2, wherein in the case of effecting two or more cold rolling steps, annealing at a temperature of 850.degree.-1,100.degree.C corresponding to the number of times of the repeated cold rolling steps is effected between the cold rolling steps. 4. A method of manufacturing single-oriented electrical steel sheet as defined in claim 2, wherein the final cold rolling rate is 50 to 77%. 5. A method of manufacturing single-oriented electrical steel sheet as defined in claim 2, wherein the final annealing for secondary recrystallization is effected at a temperature of 800.degree. to 880.degree.C. 6. A method of manufacturing single-oriented electrical steel sheet as defined in claim 2, wherein said silicon steel raw material additionally contains a positive amount of less than 0.5% of Cr, Nb, V, W, B, Ti, Zr or Ta. 7. A method of manufacturing single-oriented steel sheet as defined in claim 2, wherein the silicon steel raw material is subjected to an annealing at a temperature of 850.degree.-1,100.degree.C to produce a homogeneous texture in the hot rolled material prior to cold rolling. Other info: Inventors: Imanaka, Takuichi (Chiba, JA) Kan, Takahiro (Chiba, JA) Obata, Yoshio (Chiba, JA) Sato, Toru (Chiba, JA) Application Number: 404776 Filing Date: 1973-10-09 Publication_date: 1976-01-13 Assignee: Kawasaki Steel Corporation (Kobe, JA) Primary Class(es): 148/112 148/111, 148/308 Other Classes: US Patent Ref:
Other Refs:
Saito, T; Effect of Minor Elements . . . on Secondary Recrystallization, IBID, p. 191. | |