Abstract: Provided is an iron-based powder for dust cores that has high apparent density and enables producing dust cores having high green density. An iron-based powder for dust cores comprises a maximum particle size of 1 mm or less, wherein a median circularity of particles constituting the iron-based powder for dust cores is 0.40 or more, and a uniformity number in Rosin-Rammler equation is 0.30 or more and 90.0 or less.

Abstract: A heater of the disclosure includes: a rod-like ceramic body; a heat-generating resistor including an embedded portion embedded in the ceramic body and an exposed portion drawn out to an outer periphery face of the ceramic body; a metallic member electrically connected to the heat-generating resistor; and a conductive joining member including titanium, the conductive joining member being configured to join the exposed portion and the metallic member together. The conductive joining member includes a first portion in layer form, in which titanium exists in segregation condition, located along an interface with the exposed portion; and at least one second portion in granular form, in which titanium exists in segregation condition, located away from the first portion.

Abstract: Disclosed is an alloyed steel powder for powder metallurgy from which sintered parts that do not contain expensive Ni, or Cr or Mn susceptible to oxidation, that have excellent compressibility, and that have high strength in an as-sintered state can be obtained. The alloyed steel powder for powder metallurgy has: a chemical composition containing Cu: 1.0 mass % to 8.0 mass %, with the balance being Fe and inevitable impurities; and constituent particles in which Cu is present in an precipitated state with an average particle size of 10 nm or more.

Abstract: 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 FeaSibBcPdCueMf, 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.

Abstract: Provided is an iron-based alloy sintered body having a tensile strength of 800 MPa or more, excellent machinability, a microstructure with an average Vickers hardness of 300 Hv or more and 900 Hv or less and a standard deviation of Vickers hardness of 200 Hv or less, and an average pore circularity of 0.30 or more.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream is higher than the melting point by 100° C. or more, spraying primary cooling water from a plurality of directions at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream of the primary cooling water from one direction and an impact direction on the molten metal stream of the primary cooling water from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+50° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

Abstract: 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 FeaSibBcPdCueMf, 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.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

Abstract: Provided is a soft magnetic powder that can produce a dust core having excellent magnetic properties. The soft magnetic powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of FeaSibBcPdCueMf, where the M 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 particle size is 1 mm or less, and a median of circularity of particles constituting the soft magnetic powder is 0.4 or more and 1.0 or less.

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %?2.7??(1).

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %?2.7??(1).

Abstract: Provided is alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, or Si. The alloyed steel powder includes iron-based alloy containing Mo, in which Mo content is 0.4 mass % to 1.8 mass %, a weight-based median size D50 is 40 ?m or more, and among particles contained in the alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: Disclosed is a mixed powder for powder metallurgy including: (a) an iron-based powder containing Si in an amount of 0 mass % to 0.2 mass % and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities; and (b) an alloyed steel powder containing Mo in an amount of 0.3 mass % to 4.5 mass %, Si in an amount of 0 mass % to 0.2 mass %, and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities, wherein a ratio of (b) the alloyed steel powder to a total of (a) the iron-based powder and (b) the alloyed steel powder is from 50 mass % to 90 mass %, and a ratio of Mo to the total of (a) the iron-based powder and (b) the alloyed steel powder is 0.20 mass % or more and less than 2.20 mass %.

Abstract: Provided is an iron-based alloy sintered body having a tensile strength of 800 MPa or more, excellent machinability, a microstructure with an average Vickers hardness of 300 Hv or more and 900 Hv or less and a standard deviation of Vickers hardness of 200 Hv or less, and an average pore circularity of 0.30 or more.

Abstract: Disclosed is a partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, and Si. A partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility that includes an iron-based powder and Mo diffusionally adhered to a surface of the iron-based powder, in which Mo content is 0.2 mass % to 2.0 mass %, a weight-based median diameter D50 is 40 ?m or more, and among particles contained in the partially diffusion-alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: Provided is a steel strip joining method that can appropriately evaluate risk of a fracture in a joined part and prevent a fracture more reliably. An iron-based mixed powder for powder metallurgy comprises: an iron-based alloy powder; and an alloying powder, wherein the iron-based alloy powder contains Mo: 0.2 mass % or more and 1.5 mass % or less, the alloying powder contains a graphite powder and a copper powder, a ratio of a mass of the graphite powder to a total mass of the iron-based alloy powder and the alloying powder is 0.10 mass % to 1.0 mass %, a ratio of a mass of the copper powder to the total mass of the iron-based alloy powder and the alloying powder is 0.5 mass % to 3.0 mass %, and the copper powder has an average particle size of 25 ?m or less, and a specific surface area of 0.30 m2/g or more.

Abstract: Provided is an iron-based powder for dust cores that has high apparent density and enables producing dust cores having high green density. An iron-based powder for dust cores comprises a maximum particle size of 1 mm or less, wherein a median circularity of particles constituting the iron-based powder for dust cores is 0.40 or more, and a uniformity number in Rosin-Rammler equation is 0.30 or more and 90.0 or less.

Abstract: Disclosed is an alloyed steel powder for powder metallurgy from which sintered parts that do not contain expensive Ni, or Cr or Mn susceptible to oxidation, that have excellent compressibility, and that have high strength in an as-sintered state can be obtained. The alloyed steel powder for powder metallurgy has: a chemical composition containing Mo: 0.5 mass % to 2.0 mass % and Cu: 1.0 mass % to 8.0 mass %, with the balance being Fe and inevitable impurities; and a microstructure in which an FCC phase is present at a volume fraction of 0.5% to 10.0%.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream is higher than the melting point by 100° C. or more, spraying primary cooling water from a plurality of directions at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream of the primary cooling water from one direction and an impact direction on the molten metal stream of the primary cooling water from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+50° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.