Abstract: An elastic matrix determination method and a vibration analysis method for a laminated iron core, with which it is possible to optimally determine an elastic modulus of a laminated iron core. When a vibration analysis of a laminated iron core obtained by laminating steel sheets is performed by using a configuration expression indicating a relationship between stress and strain in a matrix display by using an elastic matrix, a shear modulus in two surfaces including a laminating direction of the laminated iron core included in the elastic matrix in the configuration expression is determined in consideration of slip between laminated steel sheets.

Abstract: An elastic matrix determination method for a laminated iron core, which can optimally determine a shear modulus in two planes including a laminating direction of the laminated iron core included in an elastic matrix in a constitutive equation representing a stress-strain relationship used for vibration analysis, and also provided is a vibration analysis method. When performing a vibration analysis of a laminated iron core formed by laminating steel sheets using a constitutive equation representing a stress-strain relationship in a matrix representation, a shear modulus in two planes including a laminating direction of the laminated iron core included in an elastic matrix in the constitutive equation is determined depending on an average tightening pressure in the laminating direction of the laminated iron core.

Abstract: An elastic matrix determination method and a vibration analysis method for a laminated iron core, with which it is possible to optimally determine an elastic modulus of a laminated iron core. When a vibration analysis of a laminated iron core obtained by laminating steel sheets is performed by using a configuration expression indicating a relationship between stress and strain in a matrix display by using an elastic matrix, a shear modulus in two surfaces including a laminating direction of the laminated iron core included in the elastic matrix in the configuration expression is determined in consideration of slip between laminated steel sheets.

Abstract: A silicon steel sheet having low iron loss of high frequency has a surface layer of the steel sheet which has Si concentration higher than Si concentration of a center portion of the steel sheet. Si concentration of sheet thickness center is 3.4 wt. % or more and Si concentration of the surface layer of the steel sheet is 5 wt. % or more. Si concentration in a surface layer portion is 5 to 8 wt. %. The production method comprises siliconizing treatment and diffusing treatment. Velocity of siliconizing and diffusing are controlled, and Si concentration distribution in the sheet thickness direction of the steel sheet is controlled.

Abstract: A silicon steel sheet having low iron loss of high frequency has a surface layer of the steel sheet which has Si concentration higher than Si concentration of a center portion of the steel sheet. Si concentration of sheet thickness center is 3.4 wt. % or more and Si concentration of the surface layer of the steel sheet is 5 wt. % or more. Si concentration in a surface layer portion is 5 to 8 wt. %. The production method comprises siliconizing treatment and diffusing treatment. Velocity of siliconizing and diffusing are controlled, and Si concentration distribution in the sheet thickness direction of the steel sheet is controlled.

Abstract: A soft magnetic alloy sheet has low residual magnetic flux density. The alloy sheet comprises a base element and an alloying element having a concentration gradient in a thickness direction of the alloy sheet. The alloying element is selected from Si, Al, Ni, Co and Fe.

Abstract: The present invention provides a method of manufacturing a silicon steel sheet having grains precisely arranged in the Goss orientation, comprising the steps of preparing a steel material containing 0.01 wt % or less of C, 2.5 to 7.0 wt % of Si, 0.01 wt % or less of S, 0.01 wt % or less of Al, 0.01 wt % or less of N, subjecting the steel material to hot rolling maintained 1000.degree. C. or higher such that the temperature of the rolled material at an end of the hot rolling step falls within the range of 700.degree. to 950.degree. C., subjecting the steel material to a primary cold rolling process at a rolling reduction of 30 to 85%, annealing the steel material at a temperature of 600.degree. to 900.degree. C., subjecting the steel material to a secondary cold rolling process at a rolling reduction of 40 to 80%, annealing the steel material again at a temperature of 600.degree. to 900.degree. C.

Abstract: The present invention provides a method of manufacturing a silicon steel sheet having grains precisely arranged in the Goss orientation, comprising the steps of preparing a steel material containing 0.01 wt. % or less of C, 2.5 to 7.0 wt. % of Si, 0.01 wt. % or less of S, 0.01 wt. % or less of Al, 0.01 wt. % or less of N, subjecting the steel material to hot rolling maintained 1000.degree. C. or higher such that the temperature of the rolled material at an end of the hot rolling step falls within the range of 700 to 950.degree. C., subjecting the steel material to a primary cold rolling process at a rolling reduction of 30 to 85%, annealing the steel material at a temperature of 600.degree. to 900.degree. C., subjecting the steel material to a secondary cold rolling process at a rolling reduction of 40 to 80%, annealing the steel material again at a temperature of 600.degree.to 900.degree. C.

Abstract: Improved channel shape electrical supply track for holding and supplying electric power to electric equipments such as spot light is provided with high mechanical strength and yet refined appearance. An elongated core case of steel plate bent into a channel shape substantially of C-shape in section is covered over inner and outer surfaces with molded synthetic resin. An inner layer of the resin covering includes a pair of opposing and parallelly elongated members simultaneously molded with the layer for supporting inside the case core a pair of elongated conductive members embedded in opposing ends of the supporting members and exposed for electrical contact with plug blades of the equipment.