Abstract: There is provided an induction heating apparatus which continuously heats a steel plate using a solenoid system. The induction heating apparatus (1) includes: at least three heating coils (10A to 10D) disposed along a longitudinal direction of the steel plate to make the steel plate (2) pass through an inside thereof; and inductance adjusters (12A to 12D) disposed on electrical pathways (11) electrically connecting each of the heating coils and a power source applying a voltage to each of the heating coils and capable of generating self-induction and adjusting self-inductance in the self-induction, in which each of the inductance adjusters is disposed to cause a generation of mutual induction at least between the inductance adjusters mutually adjacent to one another.

Abstract: There is provided an induction heating apparatus which continuously heats a steel plate using a solenoid system. The induction heating apparatus (1) includes: at least three heating coils (10A to 10D) disposed along a longitudinal direction of the steel plate to make the steel plate (2) pass through an inside thereof; and inductance adjusters (12A to 12D) disposed on electrical pathways (11) electrically connecting each of the heating coils and a power source applying a voltage to each of the heating coils and capable of generating self-induction and adjusting self-inductance in the self-induction, in which each of the inductance adjusters is disposed to cause a generation of mutual induction at least between the inductance adjusters mutually adjacent to one another.

Abstract: A continuous annealing facility comprised of a heating zone, soaking zone, and cooling zone is used for continuous annealing of a steel strip having a Curie point (Tc) by an annealing temperature over Tc during which the heat treatment in the heating zone is divided into three regions, in a first heating zone, a radiant heating means using gas heating and/or a radiant heating means using electric heaters is used to heat the steel strip to less than Tc?50° C., in a next second heating zone, the heated steel strip is heated by a solenoid coil type high frequency induction heating means to a region of Tc?30° C. to Tc?5° C., and, in a final third heating zone, the heated steel strip is heated by a radiant heating means using gas heating and/or a radiant heating means using electric heaters to a treatment target temperature over Tc to thereby anneal a steel strip having a Curie point uniformly in the longitudinal direction.

Abstract: The present invention provides a method for indirect-electrification-type continuous electrolytic etching of a metal strip suitable for producing a low-core-loss, grain-oriented silicon steel sheet not susceptible to the deterioration of core loss after stress-relief annealing, and an apparatus for the indirect-electrification-type continuous electrolytic etching.

Abstract: The present invention provides a method for indirect-electrification-type continuous electrolytic etching of a metal strip suitable for producing a low-core-loss, grain-oriented silicon steel sheet not susceptible to the deterioration of core loss after stress-relief annealing, and an apparatus for the indirect-electrification-type continuous electrolytic etching.

Abstract: A non-oriented magnetic material consisting essentially of .ltoreq.0.065% C, .ltoreq.0.10% Al, 0.31 to 3.15% Si, .ltoreq.0.020% O, .ltoreq.0.01% N and B present in such amounts that the ratio of B/N is in the range of 0.5 to 2.50. The non-oriented magnetic material of this invention is produced by hot rolling a material of the above composition, subjecting the hot-rolled sheet to at least one cold-rolling step with intermediate annealing followed by a continuous annealing step and optionally a reannealing step to produce a non-oriented magnetic material.

Abstract: A non-oriented silicon steel sheet with a low watt loss value as well as uniform magnetic properties which contains 1.5-3.5% Si, an exceedingly low C content, and a low soluble Al content, and has a ratio of B to N in the range of 0.4 to 2.0, and further contains at least one rare earth element.