Provided is a raw material powder for powder metallurgy, capable of preventing stains, surface defects and decarburization of a sintered body, improving strength and density thereof. The raw material powder for powder metallurgy is for use in the production of a sintered body that is sintered at a temperature of not lower than 500° C., composed of a mixture of a metal powder and a lubricant, in which the lubricant is melamine cyanurate or terephthalic acid. Alternatively, the raw material powder for powder metallurgy is for use in the production of a sintered body that is sintered at a temperature of not lower than 500° C, composed of a mixture of a metal powder, a first lubricant and a second lubricant, in which the first lubricant is melamine cyanurate or terephthalic acid, while the second lubricant is preferably erucic acid amide or stearic acid amide.

A compound for dust core includes a metal powder including iron, a resin composition, and a metal salt, in which the metal salt is represented by R.sub.2M, R represents a saturated fatty acid group having 6 or more and 12 or less carbon atoms, and M represents at least one metal element between Ca and Ba.

A compound for dust core includes a metal powder including iron, a resin composition, and a metal salt, in which the metal salt is represented by R.sub.2M, R represents a saturated fatty acid group having 6 or more and 12 or less carbon atoms, and M represents at least one metal element between Ca and Ba.

Some implementations of the disclosure are directed to liquid metal pastes that can be used as thermal interface materials. In one implementation, a liquid metal paste configured to be applied as a thermal interface material between electronic components, includes: 92.5 wt % of 99.9 wt % of a liquid gallium or liquid gallium alloy; and 0.1 wt % to 7.5 wt % of a powder of metal particles, the metal particles including Ag, Au, Cu, W, Ti, Cr, Ni, Cu or Ni. The liquid metal paste can also include an organic compound coating a surface of the metal particles, the organic compound configured to prevent the metal particles from forming an intermetallic compound with the liquid gallium or liquid gallium alloy.

A dust core that can significantly reduce the iron loss is provided. The dust core of the present invention includes soft magnetic particles comprising pure iron or an iron alloy and a grain boundary layer existing between adjacent soft magnetic particles. The grain boundary layer has a compound layer comprising M.sub.xFe.sub.2-xSiO.sub.4 (0≤x≤1, M: one or more types of metal elements that serve as divalent cations). Such a dust core is obtained by annealing a compact. The compact is obtained by compression-molding a powder for magnetic cores. In the powder for magnetic cores, coating layers that coat the surfaces of soft magnetic particles are each composed of a composite phase in which spinel-type ferrite represented by M.sub.yFe.sub.3-yO.sub.4 (0≤y≤1, M: one or more types of metal elements that serve as divalent cations) is dispersed on a surface of a silicone resin or inside the silicone resin. The dust core after annealing exhibits a high specific resistance due to the grain boundary layer having the compound layer and can reduce both the eddy-current loss and the hysteresis loss.

A dust core that can significantly reduce the iron loss is provided. The dust core of the present invention includes soft magnetic particles comprising pure iron or an iron alloy and a grain boundary layer existing between adjacent soft magnetic particles. The grain boundary layer has a compound layer comprising M.sub.xFe.sub.2-xSiO.sub.4 (0≤x≤1, M: one or more types of metal elements that serve as divalent cations). Such a dust core is obtained by annealing a compact. The compact is obtained by compression-molding a powder for magnetic cores. In the powder for magnetic cores, coating layers that coat the surfaces of soft magnetic particles are each composed of a composite phase in which spinel-type ferrite represented by M.sub.yFe.sub.3-yO.sub.4 (0≤y≤1, M: one or more types of metal elements that serve as divalent cations) is dispersed on a surface of a silicone resin or inside the silicone resin. The dust core after annealing exhibits a high specific resistance due to the grain boundary layer having the compound layer and can reduce both the eddy-current loss and the hysteresis loss.

A method of manufacturing a modeled body includes: modeling including applying a modeling solution to each layer of powder laid in a layer, to solidify the powder to model a solidified object; sintering the solidified object to obtain a sintered body of the solidified object; and removing a sacrificial body from the sintered body, to obtain a modeled body. At the modeling, the modeling solution is applied to a modeled body area in the solidified object and a border area in the solidified object such that, after the modeling solution is applied, a density of the powder at the border area is smaller than a density of the powder in the modeled body area. The modeled body area corresponds to the modeled body. The border area corresponds to a border between the modeled body and the sacrificial body.

A composite magnetic body according to one aspect of the present invention includes a first metal magnetic particle covered with a first resin portion made of a first resin material and a second metal magnetic particle having a smaller particle size than the first metal magnetic particle, where the second metal magnetic particle is bound to the first metal magnetic particle via a second resin portion made of a second resin material, the second resin material having a softening point higher than the first resin material.

A composite magnetic body according to one aspect of the present invention includes a first metal magnetic particle covered with a first resin portion made of a first resin material and a second metal magnetic particle having a smaller particle size than the first metal magnetic particle, where the second metal magnetic particle is bound to the first metal magnetic particle via a second resin portion made of a second resin material, the second resin material having a softening point higher than the first resin material.

A composite magnetic body according to one aspect of the present invention includes a first metal magnetic particle covered with a first resin portion made of a first resin material and a second metal magnetic particle having a smaller particle size than the first metal magnetic particle, where the second metal magnetic particle is bound to the first metal magnetic particle via a second resin portion made of a second resin material, the second resin material having a softening point higher than the first resin material.