Method for manufacturing hot-rolled steel sheet for non-oriented electromagnetic steel sheet and method for manufacturing non-oriented electromagnetic steel sheet

Abstract

The present invention provides a manufacturing method of a hot-rolled steel sheet for non-oriented electromagnetic steel sheet having good magnetic characteristics. The manufacturing method of a hot-rolled steel sheet for non-oriented electromagnetic steel sheet of the present invention includes a step of continuously casting a slab having a thickness of 30 mm to 180 mm from molten steel having a prescribed composition, and a step of subjecting the slab to hot-rolling, wherein the time from the addition of Ca to the molten steel to the casting is 150 seconds or more, the surface temperature of the slab is maintained at 850°C or more during the period from the obtaining of the slab to the delivery to the inlet side of a hot-rolling mill, and the surface temperature of the slab at the inlet side of the hot-rolling mill is set to 950°C or more, the hot-rolling is performed under conditions including 2 or more passes, the strain rate of the first pass being 5.0 / second or less, and the steel sheet is heated to 950°C or more by a bar heater between the first pass and the second pass.

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