A metal detectible plastic material, including a plurality of plastic particles defining a plastic portion and a plurality of high magnetic permeability metallic particles distributed throughout the plastic portion to define an admixture. The plastic particles and the metallic particles are generally the same size and shape, and each respective high magnetic permeability metallic particle has a magnetic permeability of at least 0.0001 H/m. The plastic particles are selected from the group consisting of high molecular mass polymers, thermoplastics, thermosetting polymers, amorphous plastics, crystalline plastics, resin-based materials, and combinations thereof.

A magnetic structural body contains core-shell structure particles each including a core section and a shell section covering the surface of the core section. The core section is made of an alloy containing a first metal and a second metal. The shell section is made of an alloy which contains the first metal and the second metal and which has a first metal-to-second metal content ratio different from that of the core section. The first metal is a magnetic metal and has a standard redox potential higher than that of the second metal. The neighboring core-shell structure particles are linearly linked to each other.

A pressed powder material of the embodiments is a pressed powder material including: a plurality of flaky magnetic metal particles, each flaky magnetic metal particle having a flat surface and a magnetic metal phase containing at least one first element selected from the group consisting of Fe, Co, and Ni, the flaky magnetic metal particles having an average thickness of from 10 nm to 100 m and an average value of the ratio of the average length in the flat surface to the thickness of from 5 to 10,000; and an intercalated phase existing between the flaky magnetic metal particles and containing at least one second element selected from the group consisting of oxygen (O), carbon (C), nitrogen (N), and fluorine (F), in which the pressed powder material includes a plane, and in which the pressed powder material includes, in a predetermined cross-section perpendicular to the flat surfaces, a void site at the boundary part between the flat surface of a flaky magnetic metal particle and the intercalated phase in contact with the flat surface, and the ratio of the length of the void site is 20% or less with respect to the length of the flat surface.

Provided are: a novel magnetic material having high magnetic stability, in particular, having an extremely high saturation magnetization; and a method for producing the same, wherein the magnetic material, due to having a higher saturation magnetization than ferrite magnetic materials and a higher electrical resistivity than existing metallic magnetic materials, resolves problems such as eddy current loss. According to the present invention, Co-ferrite nanoparticles obtained by wet synthesis are reduced in hydrogen and subjected to grain growth, and bcc- or fcc-(Fe, Co) phases and Co-enriched phases are nano-dispersed using phase separation via a disproportionation reaction to prepare a magnetic material powder. In addition, the magnetic material powder is sintered into a solid magnetic material.

The magnetic composite material of the embodiments is a magnetic composite material that includes a magnetic material having a plane at the surface; and a plate-shaped reinforcing material, the magnetic material having a plurality of magnetic bodies having a planar structure and having a magnetic metal phase containing at least one first element selected from the group consisting of iron (Fe), cobalt (Co), and nickel (Ni), and principal surfaces; and an intercalated phase containing at least one second element selected from the group consisting of oxygen (O), carbon (C), nitrogen (N), and fluorine (F). In the magnetic composite material, the principal surfaces are oriented to be approximately parallel to the plane and have the difference in coercivity on the basis of direction within the plane.

Flaky magnetic metal particles of embodiments each have a flat surface and a magnetic metal phase containing iron (Fe), cobalt (Co), and silicon (Si). An amount of Co is from 0.001 at % to 80 at % with respect to the total amount of Fe and Co. An amount of Si is from 0.001 at % to 30 at % with respect to the total amount of the magnetic metal phase. The flaky magnetic metal particles have an average thickness of from 10 nm to 100 m. An average value of the ratio of the average length in the flat surface with respect to a thickness in each of the flaky magnetic metal particles is from 5 to 10,000. The flaky magnetic metal particles have the difference in coercivity on the basis of direction within the flat surface.

A soft magnetic material for soft magnetic particles with a high filling rate. The soft magnetic material contains first soft magnetic particles and second soft magnetic particles with a larger average particle size than the first soft magnetic particles. The first soft magnetic particles have an average particle size in the range of 0.5 to 10 ?m, and the first soft magnetic particles have a nonpolar hydrocarbon group on their surfaces.

Disclosed is a soft magnetic powder including a main component represented by composition formula: (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. X1 represents one or more selected from the group consisting of Co and Ni; X2 represents one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, and rare earth elements; and M represents one or more selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti, and V. The following relations are satisfied: 0a0.140; 0.020<b0.200; 0<c0.150; 0d0.060; 0e0.030; 0f0.010; 0; 0; and 0+0.50. An oxygen content ratio in the soft magnetic powder is from 300 ppm to 3,000 ppm as a mass ratio.

Provided are a new, highly magnetically stable magnetic material which has higher saturation magnetization than ferrite-based magnetic materials, and with which problems of eddy current loss and the like can be solved due to higher electric resistivity than that of existing metal-based magnetic materials, and a method for manufacturing the same. A magnetic material powder is obtained by reducing in hydrogen Ni-ferrite nanoparticies obtained by wet synthesis and causing grain growth, while simultaneously causing nanodispersion of an -(Fe, Ni) phase and an Ni-enriched phase by means of a phase dissociation phenomenon due to disproportional reaction. The powder is sintered to obtain a solid magnetic material.

An embodiment provides a magnetic core comprising a first powder and a second powder, wherein the hardness of the first powder is lower than that of the second powder, and the volume of the first powder is 40% to 60% with respect to the combined volume of the first powder and the second powder.