Abstract: A high-strength high-ductility steel sheet has a specific component composition and a steel microstructure containing, in terms of an area ratio relative to the entire microstructure, 8% or more of a retained austenite, with the remainder being at least one of bainite, martensite, tempered bainite, and tempered martensite. With respect to the carbon concentration in the retained austenite, an average carbon concentration is from 0.9 to 1.2 mass %, a standard deviation of the carbon concentration distribution is 0.35 mass % or more, and an area ratio of a region having the carbon concentration of 1.5 mass % or more, relative to the entire microstructure, is 1.0% or more.

Abstract: A solenoid valve is provided which can be reduced in size while allowing a plunger and a shaft to slide smoothly. A solenoid valve includes a solenoid portion with a plunger that moves in an axial direction using a magnetic force generated by a solenoid coil. The solenoid portion has a cover member that houses the plunger, a shaft that is movable in the axial direction along with the plunger, and a core member that attracts the plunger in the axial direction. The shaft is supported by a first bearing portion formed on a cylindrical portion of the core member and a second bearing portion formed on a second bottom portion of the cover member such that the shaft is movable in the axial direction.

Abstract: In a steel sheet having a specific chemical composition and having a microstructure including ferrite that is a soft first phase by 20-50% in terms of the area ratio, the remainder being tempered martensite and/or tempered bainite that is a hard second phase, the microstructure of steel of a surface layer section of the steel sheet from the surface to the depth of 100 ?m and a center section of t/4-3t/4 (t is the sheet thickness) is controlled.

Abstract: This high-strength hot-rolled steel plate contains specific amounts of C, Si, Mn, Al, V and also Ti and/or Nb so as to fulfill C?12(V/51+Ti/48+Nb/93)>0.03, and the rest consists of iron and unavoidable impurities. Ferrite is the main microstructure, the remaining microstructure is one or more selected from the group consisting of bainite, martensite and retained austenite, wherein the average particle diameter of precipitated carbides (the total content of V, Ti and Nb is 0.02% or greater) in the ferrite is less than 6 nm.

Abstract: This high-strength steel plate has a component composition including, by mass %, C: 0.02-0.3%, Si: 1-3%, Mn: 1.8-3%, P: 0.1% or less, S: 0.01% or less, Al: 0.001-0.1%, N: 0.002-0.03%, the rest consisting of iron and impurities. Said steel plate has a microstructure including, in terms of area ratio relative to the entire microstructure, each of the following phases: bainitic ferrite: 50-85%; retained ?: 3% or greater; martensite+the aforementioned retained ?: 10-45%; and ferrite: 5-40%. The C concentration (C?R) in the aforementioned retained austenite is 0.3-1.2 mass %, part or all of the N in the aforementioned component composition is solid solution N, and the amount of said solid solution N is 30-100 ppm.

Abstract: A solenoid valve includes a sleeve, a spool valve, and a solenoid part. The solenoid part has an electromagnetic coil, a solenoid core, a plunger that moves in the axial direction with respect to the solenoid core, and a stopper that is interposed between the plunger and the solenoid core to restrict movement of the plunger. The solenoid core includes a cylindrical part and an extended part. The cylindrical part has an opposing surface facing the plunger in the axial direction and a contact surface that is contacted by the stopper. The extended part is extended in the axial direction from an outer peripheral end of the cylindrical part. At least a part of the opposing surface of the cylindrical part is located closer to the plunger than the contact surface.

Abstract: Provided is a hot-press molded article that can achieve a high level of balance between high strength and extension by region and has a region corresponding to an energy absorption site and a shock resistant site within a single molded article without applying a welding method by means of having first region having a metal structure containing both 80-97 area % of martensite and 3-20 area % of residual austenite, the remaining structure comprising no more than 5 area %, and a second region having a metal structure comprising 30-80 area % of ferrite, less than 30 area % (exclusive of 0 area %) of bainitic ferrite, no greater than 30 area % (exclusive of 0 area %) of martensite, and 3-20 area % of residual austenite.

Abstract: In a high strength cold-rolled steel plate having a specific chemical composition, a soft first phase (ferrite) has an area ratio of 20-50%, the remainder being a hard second phase (tempered martensite and/or tempered bainite), among all the ferrite grains, ferrite grains that have an average grain diameter of 10-25 ?m account for a total area ratio of 80% or more, the number of the cementite grains that have an equivalent circle diameter of 0.3 ?m or more is more than 0.15 piece and 1.0 piece or less per 1 ?m2 of ferrite, and the tensile strength is 980 MPa or more.

Abstract: The present disclosure relates to a high-strength hot-dip galvannealed steel sheet excellent in bake hardenability and bendability and having a component composition containing, in mass %, C: from 0.05 to 030%, Si: from 0.5 to 3.0%, Mn: from 0.2 to 3.0%, P: from 0 to 0.10%, S: from 0 to 0.010%, N: form 0 to 0.010%, and Al: from 0.001 to 0.10%, with the remainder being iron and unavoidable impurities. The steel sheet has a steel structure containing, in terms of area percentage, martensite: form 50 to 85% and ferrite: 0% or more and less than 5%, with the remainder being bainite. The steel sheet has a dislocation density of 5.0×1015 m?2 or more, a solute carbon amount of 0.08 mass % or more and a tensile strength of 1180 MPa or more.

Abstract: A high-strength cold-rolled steel sheet has a chemical composition including C of 0.05% to 0.30%, Si of greater than 0% to 3.0%, Mn of 0.1% to 5.0%, P of greater than 0% to 0.1%, S of greater than 0% to 0.02%, Al of 0.01% to 1.0%, and N of greater than 0% to 0.01%, in mass percent, with the remainder including iron and inevitable impurities. The steel sheet has a microstructure containing ferrite as a soft primary phase in an area percentage of 20% to 50% with the remainder including tempered martensite and/or tempered bainite as a hard secondary phase. The ferrite grains are adapted to contain cementite particles having an appropriate size in an appropriate number density.

Abstract: There is provided a hot press-formed product, including a thin steel sheet formed by a hot press-forming method, and having a metallic structure that contains bainitic ferrite at 70% to 97% by area, martensite at 27% by area or lower, and retained austenite at 3% to 20% by area, the remainder structure of which is at 5% by area or lower, whereby balance between strength and elongation can be controlled in a proper range and high ductility can be achieved.

Abstract: There is provided a hot press-formed product, including a thin steel sheet formed by a hot press-forming method, and having a metallic structure that contains retained austenite at 3% to 20% by volume, whereby balance between strength and elongation can be controlled in a proper range and high ductility can be achieved.

Abstract: A steel sheet for hot-pressing includes a specific chemical component composition. In the steel sheet, an average equivalent-circle diameter of a Ti-containing precipitate having an equivalent-circle diameter of 30 nm or less among Ti-containing precipitates contained in the steel sheet is 3 nm or more. In the steel, a precipitated Ti amount and a total Ti amount in a steel satisfy the relationship of: Precipitated Ti amount (mass %)?3.4[N]?0.5×[(total Ti amount (mass %))?3.4[N]] in which [N] indicates the content (mass %) of N in the steel. In the steel sheet, a ferrite fraction in a metal microstructure is 30 area % or more.

Abstract: A method for manufacturing a press-formed article includes: heating a specific steel sheet for hot-pressing at 900° C. or more and 1,100° C. or less; starting press forming of the steel sheet which has been heated; and then, cooling the steel sheet to a temperature equal to or less than a temperature 100° C. below a bainite transformation starting temperature Bs and equal to or more than a martensite transformation starting temperature Ms, while ensuring an average cooling rate of 20° C./sec or more in a mold during forming and after the completion of forming; and further cooling the steel sheet, which has been cooled, to 200° C. or less at an average cooling rate of less than 20° C./sec.

Abstract: Provided is a hot-pressing steel plate useful for obtaining a press-molded article having excellent anti-softening characteristics in heat-affected zones (HAZ) while attaining a press-molded article that can achieve a high level of balance between high strength and stretchability if uniform characteristics within the molded article are required, and a high level of balance between high strength and stretchability in respective regions if regions corresponding to shock-resistant portions and energy-absorbing portions are required within one molded article; molding and processing prior to hot-pressing being facilitated by the hot-pressing steel plate having a prescribed chemical composition, having the equivalent circular diameter of Ti-containing deposits included in the steel plate be 30 nm or less with the average equivalent circular diameter of the Ti-containing deposits being 6 nm or less, having the deposited Ti amount and the total Ti amount within the steel satisfy a prescribed relation, and having a me

Abstract: A solenoid valve is provided which can be reduced in size while allowing a plunger and a shaft to slide smoothly. A solenoid valve includes a solenoid portion with a plunger that moves in an axial direction using a magnetic force generated by a solenoid coil. The solenoid portion has a cover member that houses the plunger, a shaft that is movable in the axial direction along with the plunger, and a core member that attracts the plunger in the axial direction. The shaft is supported by a first bearing portion formed on a cylindrical portion of the core member and a second bearing portion formed on a second bottom portion of the cover member such that the shaft is movable in the axial direction.

Abstract: The purpose of the present invention is to provide a spot welded joint with superior joint strength even when the welded joint is obtained by spot welding high strength steel plates to each other. The spot welded joint is a welded joint obtained by superimposing and spot welding two steel plates with plate thicknesses t1 and t2 and is characterized by the diameter of the nuggets formed by spot welding being 3?{(t1+t2)/2} or greater (the units for the nugget diameter, t1 and t2 being nun), and, at the cross-sectional surface in the direction of plate thickness, the radius of curvature for both ends in the direction of diameter of the nugget being 0.3(t1+t2) or greater.

Abstract: A solenoid valve includes: a sleeve having a supply port and an output port; a spool valve that is housed in a valve hole formed in the sleeve so as to be movable in the axial direction, and that changes a flow passage area between the supply port and the output port by moving in the axial direction; a solenoid portion that pushes the spool valve toward one axial side; and a coil spring that urges the spool valve toward the solenoid portion. A housing hole that is a bottomed hole is formed in the spool valve, and a columnar piston member is slidably housed in the housing hole. The spool valve has an introduction hole through which a pressure of the hydraulic fluid output from the output port is introduced into a space between a bottom face of the housing hole and one end face of the piston member.

Abstract: A hot press molding including: a first forming region exhibiting a metal structure, which contains 80-97 area % of martensite and 3-20 area % of retained austenite, respectively, and in which the residual structure is 5 area % or less; and a second forming region exhibiting a metal structure, which contains 70-97 area % of bainitic ferrite, 27 area % or less of martensite, and 3-20 area % of retained austenite, respectively, and in which the residual structure is 5 area % or less. As a result, hot press moldings, which have at least a region corresponding to a shock-resistant area and a region corresponding to an energy-absorbing area in a single molding and in which a high level of balancing of high strength with elongation according to the respective region can be achieved, are provided without using a welding method.

Abstract: A high strength cold-rolled steel sheet has a component composition containing specific amounts of C, Si, Mn, P, S, N and Al, respectively with a remainder being iron and inevitable impurities. The steel sheet contains 95% or more of martensite in terms of area ratio, and contains 5% or less (inclusive of 0%) of residual austenite and ferrite in terms of a total area ratio. An average size of a carbide is 60 nm or less in terms of an equivalent circle diameter, and a number density of the carbide having the equivalent circle diameter of 25 nm or more is 5.0×105 pieces or less per mm2. The steel sheet has a yield strength of 1,180 MPa or more and a tensile strength of 1,470 MPa or more.