Soft magnetic powder

1. A soft magnetic powder comprising a particle having no hollow part as a main component, wherein a number of hollow particles present in a region of 2.5 mm square is 40 or less and 7 or more in a cross section of a molded body obtained by powder-compacting and molding the soft magnetic powder so as to have a volume filling rate of 75% to 77%,

wherein the soft magnetic powder is manufactured by pulverizing a molten metal of a mother alloy with a jet gas by a gas atomization process to form the soft magnetic powder, and

wherein a weight-basis value of a flow rate of the molten metal divided by a volumetric-basis flow rate of the jet gas is 0.2 g/L or more and 3.1 g/L or less.

2. The soft magnetic powder according to claim 1 , wherein the soft magnetic powder comprises an alloy composition comprising Fe as a main component; a sum of contents of Fe, Co and Ni in the alloy composition is 72 atom % to 85 atom % where the contents of Co and/or Ni may be 0 atom %; and the soft magnetic powder comprises an amorphous structure.

3. The soft magnetic powder according to claim 2 , wherein the soft magnetic powder has an average particle diameter of 10 μm to 70 μm.

4. A coil component comprising a magnetic body part which comprises the soft magnetic powder according to claim 2 and a resin, and a coil conductor embedded in the magnetic body part, wherein a content of the soft magnetic powder in the magnetic body part is 60% by volume or more.

5. A coil component comprising a magnetic core which comprises the soft magnetic powder according to claim 2 and a resin, and a coil conductor wound around the magnetic core, wherein a content of the soft magnetic powder in the magnetic core is 60% by volume or more.

6. The soft magnetic powder according to claim 2 , wherein, in the alloy composition, a content of Fe is 70 atom % to 85 atom %, a content of Ni is 0 atom % to 6 atom %, a content of Co is 0 atom % to 6 atom %, a content of Si is more than 0 atom % and 9 atom % or less, and a content of B is more than 0 atom % and 10 atom % or less.

7. The soft magnetic powder according to claim 2 , wherein in the alloy composition, a content of Cu is 0 atom % to 0.7 atom %.

8. The soft magnetic powder according to claim 2 , wherein the alloy composition comprises Fe, Si, B, P and Cu.

9. The soft magnetic powder according to claim 2 , wherein the alloy composition comprises at least one selected from a group consisting of Fe, Si, B, P, Ni and Co.

10. The soft magnetic powder according to claim 1 , wherein the soft magnetic powder has an average particle diameter of 10 μm to 70 μm.

11. A coil component comprising a magnetic body part which comprises the soft magnetic powder according to claim 10 and a resin, and a coil conductor embedded in the magnetic body part, wherein a content of the soft magnetic powder in the magnetic body part is 60% by volume or more.

12. A coil component comprising a magnetic core which comprises the soft magnetic powder according to claim 10 and a resin, and a coil conductor wound around the magnetic core, wherein a content of the soft magnetic powder in the magnetic core is 60% by volume or more.

13. A coil component comprising a magnetic body part which comprises the soft magnetic powder according to claim 1 and a resin, and a coil conductor embedded in the magnetic body part, wherein a content of the soft magnetic powder in the magnetic body part is 60% by volume or more.

14. A coil component comprising a magnetic core which comprises the soft magnetic powder according to claim 1 and a resin, and a coil conductor wound around the magnetic core, wherein a content of the soft magnetic powder in the magnetic core is 60% by volume or more.

15. A method for manufacturing the soft magnetic powder according to claim 1 , comprising pulverizing a molten metal of a mother alloy with a jet gas by a gas atomization process followed by water cooling to form the soft magnetic powder, and wherein a weight-basis value of a flower rate of the molten metal divided by a volumetric-basis flow rate of the jet gas is 0.2 g/L or more and 3.1 g/L or less.

16. The method according to claim 15 , wherein the mother alloy comprises Fe as a main component; and a sum of contents of Fe, Co and Ni in the mother alloy is 72 atom % to 85 atom % where the contents of Co and/or Ni may be 0 atom %.

17. The method according to claim 15 , wherein the jet gas comprises an inert gas.

18. A method for manufacturing the soft magnetic powder according to claim 1 , comprising pulverizing a molten metal of a mother alloy with a jet gas by a gas atomization process to form the soft magnetic powder, and wherein a weight-basis value of a flow rate of the molten metal divided by a volumetric-basis flow rate of the jet gas is 0.2 g/L or more and 3.1 g/L or less;

wherein the mother alloy comprises Fe as a main component; and a sum of contents of Fe, Co and Ni in the mother alloy is 72 atom % to 85 atom % where the contents of Co and/or Ni may be 0 atom %.

19. The method according to claim 18 , wherein the jet gas comprises an inert gas.

20. A method for manufacturing the soft magnetic powder according to claim 1 , comprising pulverizing a molten metal of a mother alloy with a jet gas by a gas atomization process to form the soft magnetic powder, and wherein a weight-basis value of a flow rate of the molten metal divided by a volumetric-basis flow rate of the jet gas is 0.2 g/L or more and 3.1 g/L or less; and wherein the jet gas comprises an inert gas.

21. The method according to claim 20 , wherein the jet gas comprises Ar and/or N 2 .

22. The method according to claim 21 , wherein the jet gas comprises H 2 of 0.5% to 7% in terms of partial pressure.

23. The method according to claim 20 , wherein the jet gas comprises H 2 of 0.5% to 7% in terms of partial pressure.