The present invention relates to an electromagnetic shielding sheet capable of improving reliability. Particularly, the present invention provides a composite magnetic sheet for electromagnetic shielding structured such that an independent soft magnetic sheet, which has a low surface roughness, is laminated on the outermost surface of a soft magnetic sheet having a lamination structure, thereby implementing laminated composite sheets having different surface roughness or porosity characteristics; as a result, the reliability in an external hazardous environment, such as saline water, can be substantially enhanced while maintaining the efficiency of electromagnetic shielding.

In order to provide a soft magnetic flaky powder having high electrical resistance and high corrosion resistance, and a magnetic sheet including the same, the present invention provides a soft magnetic flaky powder, including a plurality of soft magnetic flaky particles. Each of the plurality of soft magnetic flaky particles contains an Fe-based alloy flaky particle and a coating layer formed on a surface of the Fe-based alloy flaky particle. The coating layer contains one or two or more components selected from chromic acid and a hydrate thereof, and a metal salt of an inorganic acid and a hydrate thereof. The inorganic acid is selected from sulfuric acid, nitric acid, chromic acid, phosphoric acid, hydrofluoric acid and acetic acid. The metal salt is selected from a Na salt, an Al salt, a Ti salt, a Cr salt, a Ni salt, a Ga salt and a Zr salt. The coating layer has a thickness of 10 nm or more.

A non-oriented electrical steel sheet having a high magnetic flux density and a low iron loss includes C: not more than 0.01 mass %, Si: 1.3-5.0 mass %, Mn: 0.001-3 mass %, sol. Al: not more than 0.004 mass %, P: 0.03-0.20 mass %, S: not more than 0.005 mass %, N: not more than 0.005 mass %, Ti: more than 0.0020 mass % but not more than 0.1 mass %, and further contains one or more selected from Sn: 0.001-0.1 mass %, Sb: 0.001-0.1 mass %, Ca: 0.001-0.02 mass % and Mg: 0.001-0.02 mass % as required.

A non-oriented electrical steel sheet containing: in mass %, C: 0.005% or less; Si: 0.1% to 2.0%; Mn: 0.05% to 0.6%; P: 0.100% or less; and Al: 0.5% or less, in which 10 pieces/μm.sup.3 or less in number density of non-magnetic precipitate AlN having an average diameter of 10 nm to 200 nm are contained, and an average magnetic flux density B50 in a rolling direction and in a direction perpendicular to rolling is 1.75 T or more. This non-oriented electrical steel sheet can be manufactured by two methods of a method of performing hot rolling annealing at a temperature of 750° C. to an Ac1 transformation point and a method of setting a coil winding temperature to 780° C. or higher and performing self annealing.

According to an aspect of the present invention, a wireless power transmitting apparatus of a wireless charging system includes a substrate, a first bonding layer formed on the substrate, a soft magnetic layer formed on the first bonding layer, a second bonding layer formed on the soft magnetic layer and a transmitting coil formed on the second bonding layer, wherein at least one of the first bonding layer and the second bonding layer includes a magnetic substance.

Provided is soft magnetic powder used to manufacture a dust core having good mechanical strength and superior formability while iron loss is reduced. The soft magnetic powder for dust cores according to the invention is soft magnetic mixed powder that includes pure iron powder and soft magnetic iron-base alloy powder, wherein the proportion of the soft magnetic iron-base alloy powder in the mixture is 5 to 60 mass %, the ratio of the modes of the particle size distributions of the soft magnetic iron-base alloy powder and the pure iron powder ((the mode of the particle size distribution of the soft magnetic iron-base alloy powder)/(the mode of the particle size distribution of the pure iron powder)) is 0.9 or more and less than 5, and the ratio R.sub.over/R.sub.under is 1.2 or more, where R.sub.over is the mass proportion of soft magnetic iron-base alloy powder in mixed powder with a particle size of D50 or more based on the mass fraction, and R.sub.under is the mass proportion of soft magnetic iron-base alloy powder in mixed powder with a particle size of less than D50 based on the mass fraction.

A soft magnetic resin composition contains flat soft magnetic particles, and a resin component containing an epoxy resin, a phenol resin, and an acrylic resin. The epoxy resin consists of only an epoxy resin having three or more functional groups, the phenol resin consists of only a phenol resin having three or more functional groups, and the content ratio of the acrylic resin in the resin component is 25 mass % or more.

A non-oriented electrical steel sheet has a chemical composition having C: not more than 0.005 mass %, Si: 2-7 mass %, Mn: 0.033 mass %, Al: not more than 3 mass %, P: not more than 0.2 mass %, S: not more than 0.005 mass %, N: not more than 0.005 mass %, Se: 0.0001˜0.0005 mass %, As: 0.0005˜0.005 mass % and the remainder being Fe and inevitable impurities, and an iron loss W.sub.15/50 in excitation at 50 Hz and 1.5 T of not more than 3.5 W/kg and a ratio (x/t) of amount of shear drop x (mm) to thickness t (mm) in punching of steel sheet of not more than 0.15 and is excellent in the iron loss property before punching and less in the deterioration of the iron loss property by punching.

A powder magnetic core having excellent specific resistance or strength. The powder magnetic core has soft magnetic particles, first coating layers that coat the surfaces of the soft magnetic particles and include aluminum nitride, and second coating layers that coat at least a part of the surfaces of the first coating layers and include a low-melting-point glass having a softening point lower than an annealing temperature for the soft magnetic particles. The first coating layers including aluminum nitride are excellent in the wettability to the low-melting-point glass which constitutes the second coating layers and suppress diffusion of constitutional elements between the soft magnetic particles and the low-melting-point glass of the second coating layers. The powder magnetic core can stably exhibit a higher specific resistance and higher strength than the prior art owing to such a synergistic action of the first coating layers and second coating layers.

A method produces a high strength electrical steel sheet in which a cumulative rolling reduction ratio in rough rolling is 73.0% or more, in which in a hot band annealing step, an annealing condition is selected that satisfies an area ratio of recrystallized grains after hot band annealing of 100%, and a recrystallized grain size of 80 μm to 300 μm, under a condition where annealing temperature is 850° C. to 1000° C., and annealing duration is 10 seconds to 10 minutes, and in which in a final annealing step, an annealing condition is selected that satisfies an area ratio of recrystallized grains after the final annealing of 30% to 95%, and a length in the rolling direction of a connected non-recrystallized grain group of 2.5 mm or less, under a condition where annealing temperature is 670° C. to 800° C., and annealing duration is 2 seconds to 1 minute.