According to an aspect of the present disclosure, a heat-resistant coating composition includes: an inorganic filler which is iron (Fe)-based amorphous alloy powder having an amorphous phase and an average particle diameter of 0.5 μm to 15 μm; and a binder, where the coefficient of thermal expansion of the inorganic filler is lower than the coefficient of thermal expansion of the binder.

A soft magnetic powder contains a particle having a composition represented by Fe.sub.xCu.sub.aNb.sub.b(Si.sub.1-yB.sub.y).sub.100-x-a-b, and 0.3≤a≤2.0, 2.0≤b≤4.0, and 72.5≤x≤75.5, and y is a number satisfying f(x)≤y≤0.99, and f(x)=(4×10.sup.−34)×17.56. The particle includes a crystal grain having a grain size of 1.0 nm to 30.0 nm, a Cu segregation portion, and a crystal grain boundary. A content proportion of the crystal grain is 30% or more. When the Cu segregation portion positioned in a surface layer portion and having a grain size of 1.0 nm to 5.0 nm is referred to as a first Cu segregation portion, and the Cu segregation portion positioned in an inner portion and having a grain size of 3.0 nm to 10.0 nm is referred to as a second Cu segregation portion, a number proportion of the first Cu segregation portion is 80% or more, and a number proportion of the second Cu segregation portion is 80% or more.

A soft magnetic powder contains a particle having a composition represented by Fe.sub.xCu.sub.aNb.sub.b(Si.sub.1-yB.sub.y).sub.100-x-a-b, and 0.3≤a≤2.0, 2.0≤b≤4.0, and 72.5≤x≤75.5, and y is a number satisfying f(x)≤y≤0.99, and f(x)=(4×10.sup.−34)×17.56. The particle includes a crystal grain having a grain size of 1.0 nm to 30.0 nm, a Cu segregation portion, and a crystal grain boundary. A content proportion of the crystal grain is 30% or more. When the Cu segregation portion positioned in a surface layer portion and having a grain size of 1.0 nm to 5.0 nm is referred to as a first Cu segregation portion, and the Cu segregation portion positioned in an inner portion and having a grain size of 3.0 nm to 10.0 nm is referred to as a second Cu segregation portion, a number proportion of the first Cu segregation portion is 80% or more, and a number proportion of the second Cu segregation portion is 80% or more.

A soft magnetic alloy powder includes soft magnetic alloy particles having an amorphous phase. Each of the soft magnetic alloy particles has chemical composition represented by Fe.sub.aSi.sub.bB.sub.cC.sub.dP.sub.eCu.sub.fSn.sub.gM1.sub.hM2.sub.i, where M1 is one or more elements of Co and Ni, M2 is one or more elements of Ti, Zr, Hf, Nb, Ta, Mo, W, Cr, Al, Mn, Ag, V, Zn, As, Sb, Bi, Y, and a rare earth element, and 79≤a+h+i≤86, 0≤b≤5, 7.2≤c≤12.2, 0.1≤d≤3, 7.3≤c+d≤13.2, 0.5≤e≤10, 0.4≤f≤2, 0.3≤g≤6, 0≤h≤30, 0≤i≤5, and a+b+c+d+e+f+g+h+i=100 (parts by mol) are satisfied.

A high saturation, low loss magnetic material suitable for high frequency electrical devices, including power converters, transformers, solenoids, motors, and other such devices.

A high saturation, low loss magnetic material suitable for high frequency electrical devices, including power converters, transformers, solenoids, motors, and other such devices.

Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.

Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.

Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.

An alloy particle contains: total content of Fe and Co: from 82.2 to 96.5 parts by mass; Co: 0 to 30.0 parts by mass; P: 0 to 4.5 parts by mass; B: more than 0 to 5.0 parts by mass; C: 0 to 3.0 parts by mass; Si: 0 to 6.7 parts by mass; Ni: more than 0 to 12.0 parts by mass; Cr: more than 0 to 4.2 parts by mass; total content of Mo, W, Zr, and Nb: 0 to 4.2 parts by mass; total content of P and Cr: 7.4 parts by mass or less; multiplication product of the parts by mass of Ni and Cr: 0.5 or more; and total content of Fe, Co, and Ni: 97.0 parts by mass or less. The alloy particle contains an amorphous phase, and a volume percentage of the amorphous phase is 70% or higher.