Abstract:
PROBLEM TO BE SOLVED: To reduce shape defects arising in finishing annealing, and to increase product yield.SOLUTION: There is provided a method for producing a grain-oriented electrical steel sheet by subjecting a post-cold-rolling coil for a grain-oriented electrical steel sheet to primary recrystallization annealing, applying an annealing separation agent, and performing finishing annealing, wherein in the heating step of the primary recrystallization annealing, rapid heating is performed between 500-700°C at least at 80°C/sec, and in the heating step of finishing annealing, a holding process is performed that holds for 2-100 hours between 700-1,000°C. Preferably, finishing annealing is additionally performed after laying down an insulating material onto the upper surface of a coil pedestal, which is in the annealing furnace used in finishing annealing, in a concentric manner from the outer peripheral side and at least at 20% of the radius of the coil pedestal.
Abstract:
{Problems} To provide a copper alloy sheet material, excellent in bending property and mechanical strength, and suitable for lead frames, connectors, terminal materials, and the like in electrical/electronic equipments, for connectors, for example, to be mounted on automotive vehicles, and for terminal materials, relays, switches, and the like; and to provide a method of producing the same. {Means to solve} A copper alloy sheet material, containing at least one of Cr, Zr, and Ti in an amount of 0.05 to 1.0 mass% in total, with the balance being copper and unavoidable impurities, wherein an area ratio of Cube orientation {0 0 1} is 5% or more and 70% or less, in crystal orientation analysis by an EBSD analysis, and wherein a Vickers hardness is 120 or more; and a method of producing the same.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for manufacturing a grain-oriented electromagnetic steel sheet with low iron loss.SOLUTION: The method includes a groove forming step of forming grooves on a silicon steel sheet in its width direction by irradiating a plurality of times the sheet with a laser beam while placing predetermined intervals in its passing direction during cold rolling and winding. When P(W) represents an average intensity of the laser beam; Dl (mm) represents a condensed beam diameter in the passing direction of the condensed beam spot of the laser beam; Dc (mm) represents a condensed beam diameter in the width direction thereof; Vc (mm/s) represents a scanning speed in the width direction of the laser beam; following formula 1 represents an irradiation energy density Up of the laser beam; and following formula 2 represents an instantaneous power density Ip of the laser beam, following formula 3 and formula 4 are satisfied. Formula 1: Up=(4/π)×P/(Dl×Vc). Formula 2: Ip=(4/π)×P/(Dl×Dc)×(1/1,000). Formula 3: 1≤Up≤10 (J/mm). Formula 4: 100 (kW/mm)≤Ip≤2,000 (kW/mm).
Abstract:
A predetermined steel containing Te: 0.0005 mass% to 0.0050 mass% is heated to 1320°C or lower to be subjected to hot rolling, and is subjected to annealing, cold rolling, decarburization annealing, and nitridation annealing, and thereby a decarburized nitrided steel sheet is obtained. Further, an annealing separating agent is applied on the surface of the decarburized nitrided steel sheet and finish annealing is performed, and thereby a glass coating film is formed. The N content of the decarburized nitrided steel sheet is set to 0.0150 mass% to 0.0250 mass% and the relationship of 2 × [Te] + [N] ‰¦ 0.0300 mass% is set to be established. Note that [Te] represents the Te content and [N] represents the N content.