An object is to provide a magneto-sensitive wire (magneto-sensitive body) with which the measurement range of a magnetic sensor can be expanded, the heat resistance and the high-temperature durability can be improved, and other appropriate properties can be obtained. The magneto-sensitive wire of the present invention is composed of a Co-based alloy having a composite structure in which crystal grains are dispersed in an amorphous phase. The Co-based alloy is, for example, a CoFeSiB-based alloy. In this case, the total amount of Si and B is preferably 20 to 25 at % with respect to the Co-based alloy as a whole. Preferably, the average diameter of the crystal grains is 70 nm or less and the area ratio of the crystal grains is 10% or less to the composite structure as a whole. The magneto-sensitive wire has a circular cross section, for example, and the wire diameter is about 1 to 100 m. Such a magneto-sensitive wire can be obtained, for example, through a heat treatment step of heating an amorphous wire composed of a Co-based alloy at a temperature equal to or higher than a crystallization start temperature and lower than a crystallization end temperature. This step is preferably performed while applying tensile stress to the amorphous phase.

A soft magnetic alloy powder includes a main component of (Fe.sub.(1(+))X1.sub.X2.sub.).sub.(1(a+b+c+d+e+f))M.sub.aB.sub.bP.sub.cSi.sub.dC.sub.eS.sub.f, in which X1 is one or more of Co and Ni, X2 is one or more of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements, and M is one or more of Nb, Hf, Zr, Ta, Mo, W, Ti, and V. 0a0.160, 0.020b0.200, 0c0.150, 0d0.060, 0e0.030, 0.0010f0.030, 0.005f/b1.50, 0, 0, and 0+0.50 are satisfied.

A soft magnetic alloy includes a composition of (Fe.sub.(1-(+))X1.sub.X2.sub.).sub.(1-(a+b+c+d+e+f+g))M.sub.aTi.sub.bB.sub.cP.sub.dSi.sub.eS.sub.fC.sub.g. X1 is one or more of Co and Ni. X2 is one or more of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements. M is one or more of Nb, Hf, Zr, Ta, Mo, W, and V. 0.020a+b0.140, 0.001b0.140, 0.020<c0.200, 0.010d0.150, 0e0.060, a0, f0, g0, a+b+c+d+e+f+g<1, 0, 0, and 0+0.50 are satisfied. The soft magnetic alloy has a nanohetero structure or a structure of Fe-based nanocrystalline.

An electro-acoustic transducer includes a diaphragm and an electro-magnetic motor for driving motion of the diaphragm. The electro-magnetic motor includes a magnetic circuit that includes a first Rare earth-Iron-Boron (REFeB) magnet. The REFeB magnet includes a major phase and a grain boundary rich rare earth phase. A heavy rare earth element (HREE) is diffused into the first REFeB magnet through the grain boundary rich rare earth phase.

Disclosed is an iron-based amorphous alloy Fe.sub.aB.sub.bSi.sub.cRE.sub.d, wherein a, b, and c represent, in atomic percentages, the contents of corresponding components, respectively; 83.0?a?87.0, 11.0<b<15.0, 2.0?c?4.0, and a+b+c=100; and d is the concentration of RE in the iron-based amorphous alloy, i.e. 10 ppm?d?30 ppm. The iron-based amorphous alloy has a saturation magnetic induction intensity of no less than 1.63 T, and same can be used to manufacture a magnetic core material for power transformers, motors and inverters.

A soft magnetic alloy includes a main component of (Fe.sub.(1?(?+?))X1.sub.?X2.sub.?).sub.(1?(a+b+c+d+e))M.sub.aB.sub.bP.sub.cSi.sub.dC.sub.e. X1 is one or more of Co and Ni. X2 is one or more of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements. M is one or more of Nb, Hf, Zr, Ta, Mo, W, and V. 0.020?a?0.14 is satisfied. 0.020<b?0.20 is satisfied. 0?d?0.060 is satisfied. ??0 is satisfied. ??0 is satisfied. 0??+??0.50 is satisfied. c and e are within a predetermined range. The soft magnetic alloy has a nanohetero structure or a structure of Fe based nanocrystallines.

An example system may include an electromagnet, a drive circuit electrically coupled to the electromagnet, and a controller configured to control the drive circuit to provide current to the electromagnet to generate a pulsing magnetic field. The electromagnet may include a first conductive winding, a second conductive winding, and a magnetic core. The first conductive winding may be crescent shaped. The first conductive winding may define an inner surface and an outer surface. The outer surface of the first conductive winding may include a convex portion and a concave portion. The second conductive winding may reside proximate to the concave portion of the outer surface of the first conductive winding. The outer concave segment of the first conductive winding may define a concavity, and at least a portion of the second conductive winding may reside within the concavity of the first conductive winding.

A soft magnetic alloy includes a main component of (Fe.sub.(1-(+))X1.sub.X2.sub.).sub.(1-(a+b+c+d+e+f+g))M.sub.aB.sub.bP.sub.cSi.sub.dC.sub.eS.sub.fTi.sub.g. X1 is one or more of Co and Ni. X2 is one or more of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements. M is one or more of Nb, Hf, Zr, Ta, Mo, W, and V. 0.020a0.14 is satisfied. 0.020<b0.20 is satisfied. 0d0.060 is satisfied. 0f0.010 is satisfied. 0g0.0010 is satisfied. 0 is satisfied. 0 is satisfied. 0+0.50 is satisfied. At least one or more off and g are larger than zero. c and e are within a predetermined range. The soft magnetic alloy has a nanohetero structure or a structure of Fe based nanocrystallines.

A soft magnetic alloy includes a main component of (Fe.sub.(1?(?+?))X1.sub.?X2.sub.?).sub.(1?(a+b+c+d+e))M.sub.aB.sub.bP.sub.cSi.sub.dC.sub.e. X1 is one or more of Co and Ni. X2 is one or more of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements. M is one or more of Nb, Hf, Zr, Ta, Mo, W, and V. 0.020?a?0.14 is satisfied. 0.020<b?0.20 is satisfied. 0?d?0.060 is satisfied. ??0 is satisfied. ??0 is satisfied. 0??+??0.50 is satisfied. c and e are within a predetermined range. The soft magnetic alloy has a nanohetero structure or a structure of Fe based nanocrystallines.

A coil component includes a body having a winding type coil and a core in which the winding type coil is embedded, and external electrodes disposed on external surfaces of the body. The core includes first and second cores, and the first and second cores are coupled to each other with a bonding surface interposed therebetween. The bonding surface is formed of a same type of resin as the first and second cores. The first and second cores each include a resin directly covering surfaces of magnetic powder particles, such that adjacent particles are separated only by the resin. A method of manufacturing the coil component includes applying a solvent to dissolve a resin on a bonding surface of the first core, and mounting the second core to the bonding surface having the solvent applied thereto.