Abstract: A steel near-net-shape material having high fatigue strength and high tensile strength is provided. The steel near-net-shape material has a chemical composition containing, in mass %, C: 0.03 to 0.25%, Si: 0.02 to 0.50%, Mn: more than 0.70 to 2.50%, P: 0.035% or less, S: 0.050% or less, Al: 0.005 to 0.050%, V: more than 0.10 to 0.40%, and N: 0.003 to 0.030%. The steel near-net-shape material is composed of polygonal ferrite having an area fraction of 20 to 90% and a hard phase having an area fraction of 10 to 80%, and satisfies Formula (1). A diffusible hydrogen content of the steel near-net-shape material when charged with hydrogen by a cathodic hydrogen charging method is 0.10 ppm or more. [V in precipitates]/[V]?0.

Abstract: A non-heat treated steel for induction hardening contains, in mass %, C: 0.35 to 0.44%, Si: 0.01 to less than 0.30%, Mn: 0.80 to 1.50%, P: 0.030% or less, S: more than 0.010 to 0.095%, Cr: more than 0.10 to 0.30%, V: 0.050 to 0.200%, N: 0.0040 to 0.0200%, O: 0.0024% or less, Cu: 0.05% or less and Ni: 0.05% or less, and for which fn1?50.0, fn2: 0.70 to 1.00, and fn3?1.30. In the steel, a ratio of a number of Mn oxides containing oxygen in an amount of 20.0 mass % or more and Mn in an amount of 10.0 mass % or more to the number of oxides is 10.0% or less fn1=80C2+55C+13Si+4.8Mn+30P+30S+1.5Cr fn2=C+(Si/10)+(Mn/5)?(5S/7)+(5Cr/22)+1.65V fn3=?2C—Si+2.33Mn+0.26Cr+V?1.5Cu?1.5Ni.

Abstract: There is provided a steel material that is excellent in machinability, and that provides a high roller-pitting fatigue strength, a high high-cycle bending fatigue strength, and a high low-cycle bending fatigue strength when being subjected to induction hardening to be produced into an induction-hardened component. The steel material according to the present disclosure includes a chemical composition consisting of, in mass %, C: 0.40 to 0.70%, Si: 0.15 to 2.10%, Mn: 0.30 to 1.15%, Cr: 0.01 to less than 0.50%, S: 0.005 to 0.070%, N: 0.0020 to 0.0200%, Ti: 0.0080 to 0.2000%, B: 0.0005 to 0.0050%, Al: 0.005 to 0.100%, and P: less than 0.050%, with the balance being Fe and impurities, and satisfying Formula (1) to Formula (5) described herein, and has a ferrite area fraction of 40% or less and a martensite area fraction of 10% or less.

Abstract: The steel material for a soft magnetic part according to the present invention has a chemical composition consisting of, in mass %, C: 0.02 to 0.13%, Si: 0.005 to 0.50%, Mn: 0.10 to 0.70%, P: 0.035% or less, S: 0.050% or less, Al: 0.005 to 1.300%, V: 0.02 to 0.50%, and N: 0.003 to 0.030%, with the balance being Fe and impurities. The average grain diameter of ferrite grains in the steel material for a soft magnetic part ranges from 5 to 200 ?m. Further, in the ferrite grains, the number Sv (number/mm2) of precipitates having a circle-equivalent diameter of 30 nm or more satisfies Formula (1): Sv?10V×7.0×106??(1) where the V content (mass %) in the steel material for a soft magnetic part is substituted into V in Formula (1).

Abstract: A cold forged part having a high cold forgeability and having a high endurance ratio due to work hardening by cold forging and age-hardening after cold forging, characterized by having a predetermined chemical composition, having an amount of solute Nb/amount of solute V of 0.03 or more and having a structure, by area ratio, of ferrite of 85% or more and a total of bainite and martensite of 5% or less.

Abstract: The steel material for a soft magnetic part according to the present invention has a chemical composition consisting of, in mass %, C: 0.02 to 0.13%, Si: 0.005 to 0.50%, Mn: 0.10 to 0.70%, P: 0.035% or less, S: 0.050% or less, Al: 0.005 to 1.300%, V: 0.02 to 0.50%, and N: 0.003 to 0.030%, with the balance being Fe and impurities. The average grain diameter of ferrite grains in the steel material for a soft magnetic part ranges from 5 to 200 pun. Further, in the ferrite grains, the number Sv (number/mm2) of precipitates having a circle-equivalent diameter of 30 nm or more satisfies Formula (1): Sv?10V×7.0×106??(1) where the V content (mass %) in the steel material for a soft magnetic part is substituted into V in Formula (1).

Abstract: A steel for machine structural use according to the present embodiment has a chemical composition which consists of, in mass %, C: 0.30 to 0.50%, Si: 0.01 to 0.80%, Mn: 0.20 to 2.00%, P: 0.030% or less, S: 0.010 to 0.100%, Pb: 0.010 to 0.100%, Al: 0.010 to 0.050%, N: 0.015% or less, O: 0.0005 to 0.0030% and Cr: more than 0.70% to 2.00%, with the balance being Fe and impurities, the chemical composition satisfying Formula (1). The total number of specific inclusions included in the steel which are any of MnS inclusions, Pb inclusions and composite inclusions containing MnS and Pb and which have an equivalent circular diameter of 5 ?m or more is 40 per mm2 or more. Mn/S?8.0??(1) Where, a content (mass %) of a corresponding element is substituted for each symbol of an element in Formula (1).

Abstract: A steel for machine structural use is provided which is excellent in machinability, rusting characteristics, and hot ductility. The steel for machine structural use according to the present embodiment has a chemical composition which consists of, in mass %, C: 0.30 to 0.80%, Si: 0.01 to 0.80%, Mn: 0.20 to 2.00%, P: 0.030% or less, S: 0.010 to 0.100%, Pb: 0.010 to 0.100%, Al: 0.010 to 0.050%, N: 0.015% or less and O: 0.0005 to 0.0030%, with the balance being Fe and impurities, the chemical composition satisfying Formula (1). The total number of specific inclusions included in the steel which are any of MnS inclusions, Pb inclusions and composite inclusions containing MnS and Pb and which have an equivalent circular diameter of 5 ?m or more is 40 per mm2 or more. Mn/S?8.0??(1) Where, a content (mass %) of a corresponding element is substituted for each symbol of an element in Formula (1).

Abstract: A steel for machine structural use according to the present embodiment has a chemical composition which consists of, in mass %, C: 0.15 to less than 0.30%, Si: 0.01 to 0.80%, Mn: 0.20 to 2.00%, P: 0.030% or less, S: 0.010 to 0.100%, Pb: 0.010 to 0.100%, Al: 0.010 to 0.050%, N: 0.015% or less, O: 0.0005 to 0.0030% and Cr: 0.50 to 2.00%, with the balance being Fe and impurities, the chemical composition satisfying Formula (1). The total number of specific inclusions included in the steel which are any of MnS inclusions, Pb inclusions and composite inclusions containing MnS and Pb and which have an equivalent circular diameter of 5 ?m or more is 40 per mm2 or more. Mn/S?8.0??(1) Where, a content (mass %) of a corresponding element is substituted for each symbol of an element in Formula (1).

Abstract: A non-heat treated steel for induction hardening contains, in mass %, C: 0.35 to 0.44%, Si: 0.01 to less than 0.30%, Mn: 0.80 to 1.50%, P: 0.030% or less, S: more than 0.010 to 0.095%, Cr: more than 0.10 to 0.30%, V: 0.050 to 0.200%, N: 0.0040 to 0.0200%, O: 0.0024% or less, Cu: 0.05% or less and Ni: 0.05% or less, and for which fn1?50.0, fn2: 0.70 to 1.00, and fn3?1.30. In the steel, a ratio of a number of Mn oxides containing oxygen in an amount of 20.0 mass % or more and Mn in an amount of 10.0 mass % or more to the number of oxides is 10.0% or less. fn1=80C2+55C+13Si+4.8Mn+30P+30S+1.5Cr fn2=C+(Si/10)+(Mn/5)?(5S/7)+(5Cr/22)+1.65V fn3=?2C—Si+2.33Mn+0.26Cr+V?1.5Cu?1.

Abstract: A rolled round steel material contains C: 0.38 to 0.55%, Si: 1.0% or less, Mn: 0.20 to 2.0%, S: 0.005 to 0.10%, Cr: 0.01 to 2.0%, Al: 0.003 to 0.10%, B: 0.0005 to 0.0030%, Ti: 0.047% or less, Cu: 0 to 1.0%, Ni: 0 to 3.0%, Mo: 0 to 0.50%, Nb: 0 to 0.10%, V: 0 to 0.30%, Ca: 0 to 0.005%, and Pb: 0 to 0.30%, a remaining portion being constituted by Fe and an impurities, the impurities containing P in an amount of 0.030% or less and N in an amount of 0.008% or less, and has a chemical composition satisfying [3.4N?Ti?3.4N+0.02]. The microstructure is constituted by ferrite (F), lamellar pearlite (LP), and cementite (C) and microstructural features vary in terms of the lateral, longitudinal and central portions of the steel. This steel material has a high base material toughness and good machinability without performing thermal refining.

Abstract: A cold forged part having a high cold forgeability and having a high endurance ratio due to work hardening by cold forging and age-hardening after cold forging, characterized by having a predetermined chemical composition, having an amount of solute Nb/amount of solute V of 0.03 or more and having a structure, by area ratio, of ferrite of 85% or more and a total of bainite and martensite of 5% or less.

Abstract: A rolled round steel material for a steering rack bar, having a chemical composition consisting of C: 0.38 to 0.55%, Si: not more than 1.0%, Mn: 0.20 to 2.0%, S: 0.005 to 0.10%, Cr: 0.01 to 2.0%, Al: 0.003 to 0.10%, and N: 0.003 to 0.03%, with the balance being Fe and impurities, and P being not more than 0.030% in the impurities, and a microstructure consisting of ferrite (F), lamellar pearlite (LP), and cementite (C). The average grain diameter of (F), an area fraction of (LP), and the number of particles of spheroidal cementite (SC) among C are controlled in a region from the surface to a position at ½ radius and in a central part of the material. An average aspect ratio of F is controlled in a region from a surface to a position at ½ radius.

Abstract: A rolled round steel material for a steering rack bar contains C in an amount of 0.38 to 0.55%, Si in an amount of 1.0% or less, Mn in an amount of 0.20 to 2.0%, S in an amount of 0.005 to 0.10%, Cr in an amount of 0.01 to 2.0%, Al in an amount of 0.003 to 0.10%, B in an amount of 0.0005 to 0.0030%, Ti in an amount of 0.047% or less, Cu in an amount of 0 to 1.0%, Ni in an amount of 0 to 3.0%, Mo in an amount of 0 to 0.50%, Nb in an amount of 0 to 0.10%, V in an amount of 0 to 0.30%, Ca in an amount of 0 to 0.005%, and Pb in an amount of 0 to 0.30%, a remaining portion being constituted by Fe and an impurities, the impurities containing P in an amount of 0.030% or less and N in an amount of 0.008% or less, and has a chemical composition satisfying [3.4N?Ti?3.4N+0.02].

Abstract: A rolled round steel material for a steering rack bar, having a chemical composition consisting of C: 0.38 to 0.55%, Si: not more than 1.0%, Mn: 0.20 to 2.0%, S: 0.005 to 0.10%, Cr: 0.01 to 2.0%, Al: 0.003 to 0.10%, and N: 0.003 to 0.03%, with the balance being Fe and impurities, and P being not more than 0.030% in the impurities, and a microstructure consisting of ferrite (F), lamellar pearlite (LP), and cementite (C), wherein in a cross-section perpendicular to the rolling direction: an average grain diameter of F?10 ?m, an area fraction of LP is less than 20%, and the number of particles of spheroidal cementite (SC) among C?4×105/mm2, in a region from the surface to a position at ½ radius; and an area fraction of LP?20% and the number of particles of SC<4×105/mm2, in a central part, and wherein in a cross-section including a center line of the round steel material and parallel to the rolling direction: an average aspect ratio of F is ?3 in a region from a surface to a position at ½ radius.

Abstract: Silicone surface-treated magnesium hydroxide which is surface treated by a silicone oil, the silicone oil comprising: a polyorganosiloxane containing a plurality of first siloxane units each of which contains hydrogen atom bonded silicon atom. The first siloxane units shares 50 mol % or less of total siloxane units in one molecule in average. Accordingly, sufficient fire retardancy and mechanical properties such as sufficient elongation are achieved.

Abstract: The objective of the present invention is to provide an ethylene-based composite resin composite particle having a small-sized, approximately spherical form, comprising functional filler homogeneously dispersed therein, and being compatible with other resin pellets or components. To attain the above objective, the present invention provides an environmentally friendly method for producing an ethylene-based resin composite particle, comprising: (a) dissolving ethylene-based polymer in organic solvent separable from aqueous phase and dispersing hydrophobic filler in environment-friendly organic solvent to form solution of ethylene-based polymer in the organic solvent; (b) emulsifying the solution obtained in step (a) in non-ionic surfactant-containing aqueous solution; (c) heating the emulsion obtained in step (b) to remove the organic solvent; and (d) recovering a precipitate the ethylene-based resin composite particle containing the hydrophobic filler therein.

Abstract: There are provided a composite particle comprising polystyrene and a filler, and having high levels of affinity between the filler and the polystyrene matrix, few or a small number of voids at the interface between the filler and the polystyrene matrix, and an excellent mechanical properties, and a method for preparing the same composite particle. The polystyrene-maleic anhydride/magnesium hydroxide composite particle is produced by bulk polymerization of a blend of a styrene monomer, a crosslinking agent, a polymerization initiator, maleic anhydride, and magnesium hydroxide which is coated with a surface-treatment agent in advance to impart hydrophobicity thereto, and subsequently suspension polymerization of a product obtained from the bulk polymerization.

Abstract: A steel for nitrocarburizing use, which comprises by mass percent, C: more than 0.45% to not more than 0.60%, Si<0.50%, Mn: more than 1.30% to not more than 1.70%, P?0.05%, S: 0.02 to 0.10%, Cr?0.30% and N: more than 0.007% to not more than 0.030%, and which further contains one or two elements selected from Al: more than 0.010% to not more than 0.10% and Ti: more than 0.005% to not more than 0.035%, with Al+Ti being 0.015% or more, with the balance being Fe and impurities, wherein V among the impurities is not more than 0.010%, and further satisfies the following 2 formulas, has high fatigue strength and excellent straightenability after the nitrocarburizing treatment, without performing the expensive heat treatment of quenching and tempering. Consequently, they are suitable as raw materials for nitrocarburized components: fn1=1.25C+Mn?0.1Cr, fn2=N?0.45Al?( 1/22)Ti.

Abstract: The present invention is to provide an electromagnetic wave absorption (EWA) material for thermoforming having a good formability and high EWA performance. The EWA material for thermoforming contains a EWA particle covered with a thermoplastic resin layer.