A grain-oriented electrical steel sheet has a base film composed mainly of forsterite on a surface of the grain-oriented electrical steel sheet and an insulating film containing mainly silicate-phosphate glass which is formed on a surface of the base film, in which, by controlling concentrations of Sr, Ca, and Ba in the base film and the insulating film to have specified gradients, the adhesion property and film tension of the insulating film are improved.

A grain-oriented electrical steel sheet has a base film composed mainly of forsterite on a surface of the grain-oriented electrical steel sheet and an insulating film containing mainly silicate-phosphate glass which is formed on a surface of the base film, in which, by controlling concentrations of Sr, Ca, and Ba in the base film and the insulating film to have specified gradients, the adhesion property and film tension of the insulating film are improved.

A soft magnetic alloy containing 1% by atom or more and 10% by atom or less of one or more elements M1 selected from Ga and Ge, substantially containing no Si, and containing Fe and unavoidable impurities as a balance.

A grain-oriented electrical steel sheet according to the present invention has a steel sheet surface provided with grooves and includes two or more broken lines including the grooves having a length of 5 to 10 mm on a straight line intersecting a rolling direction on the steel sheet surface. In each of the broken lines including the grooves, the grooves are arranged at equal intervals, and a ratio of the length of the groove to a length of a non-groove is in a range of 1:1 to 1.5:1.

A grain-oriented silicon steel with low iron loss, wherein the silicon steel is provided with a plurality of grooves on its surface, each of the grooves is 10-60 μm in width and 5-40 μm in depth, and the spacing between adjacent grooves is 1-10 mm. The manufacturing method therefor comprises: scoring the surface of the grain-oriented silicon steel with low iron loss by using a laser in order to form the grooves. The grain-oriented silicon steel with low iron loss can maintain the magnetic domain refining effect in a stress-relief annealing process, and avoid the introduction of more residual stress.

Provided is a non-oriented electrical steel sheet that contains substantially no Al and contains large amounts of Si and Mn and has low iron loss, comprising a chemical composition containing C: 0.0050% or less, Si: 2.0% or more and 6.0% or less, Mn: 1.0% or more and 3.0% or less, P: 0.20% or less, S: 0.0050% or less, N: 0.0050% or less, Al: 0.0050% or less, and one or more selected from B: 0.0001% or more and 0.0050% or less, Nb: 0.0001% or more and 0.0050% or less, and V: 0.0005% or more and 0.0500% or less, with a balance consisting of Fe and inevitable impurities, wherein a number density of Si—Mn nitrides with an average diameter of 50 nm or more and 500 nm or less is 1 or less per μm.sup.3.

A wireless power receiving apparatus which wirelessly charges power according to one embodiment of the present invention includes a substrate, a soft magnetic layer which is laminated on the substrate and is formed with a plurality of patterns including at least 3 lines radiated from predetermined points, and a coil which is laminated on the soft magnetic layer and receives electromagnetic energy radiated from a wireless power transmitting apparatus.

The present invention manufactures a steel sheet for a rotor core for an IPM motor, wherein the steel sheet has a magnetic flux density B.sub.8000 of 1.65 T or more as measured when magnetic field strength is 8000 A/m, and a residual magnetic flux density Br of 0.5 T or more as measured at that time, and optionally, a coercivity Hc of 100 A/m or more as measured after magnetization reaches 8000 A/m. By using the steel sheet manufactured according to the present invention for a rotor core of an IPM motor, it is possible to increase further an output torque in a high-speed rotational range and raise further the maximum rotational speed.

The present invention manufactures a steel sheet for a rotor core for an IPM motor, wherein the steel sheet has a magnetic flux density B.sub.8000 of 1.65 T or more as measured when magnetic field strength is 8000 A/m, and a residual magnetic flux density Br of 0.5 T or more as measured at that time, and optionally, a coercivity Hc of 100 A/m or more as measured after magnetization reaches 8000 A/m. By using the steel sheet manufactured according to the present invention for a rotor core of an IPM motor, it is possible to increase further an output torque in a high-speed rotational range and raise further the maximum rotational speed.

The present invention relates to a grain oriented electrical steel sheet having excellent core loss and to a method for manufacturing same. The electrical steel sheet according to one aspect of the present invention may have a composition comprising, by weight %, Si: 1.0 to 4.0%, Al: 0.1 to 4.0%, and a rare earth element: 0.0001 to 0.5% by the total content of the whole rare earth element.