| 摘要 |
PURPOSE: A method of fabricating a directional electrical sheet is provided to improve productivity as well as to secure decarbonation in a short time by annealing the electrical sheet at the final thickness. CONSTITUTION: A slab is composed of 2.0-4.0wt[ of silicon, 0.006-0.030wt% of aluminium, 0.007-0.013wt% of nitrogen, 0.025-0.055wt% of carbon, 0.3-1.0wt% of copper, less than 0.32wt% of manganese, 0.02-0.2wt% of chromium, less than 0.007wt% of sulfur and the rest of iron and other impurities. The slab is re-heated at a low temperature of 1250-1330°C and hot-rolled. After that, the slab is cold-rolled twice including a process of treating the slab at a temperature of 900-1100°C in a mixed gas atmosphere of dried hydrogen and nitrogen. After annealing the slab at a temperature of 790-850°C in a wet atmosphere, the slab is coated by an annealing parting agent and the entire area is in the mixed atmosphere of hydrogen and nitrogen. The directional electrical sheet is manufactured by finally annealing the slab at a high temperature.
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