Abstract: The present invention provides a non-oriented electrical steel sheet at low cost that has excellent magnetic properties and mechanical properties as well as excellent quality of steel sheet. The non-oriented electrical steel sheet has a chemical composition containing, by mass %, Si: 5.0% or less, Mn: 2.0% or less, Al: 2.0% or less, and P: 0.05% or less, in a range satisfying formula (1), and furthermore, C: 0.008% or more and 0.040% or less; N: 0.003% or less, and Ti: 0.04% or less, in a range satisfying formula (2), with the balance composed of Fe and incidental impurities: 300?85[Si %]+16[Mn %]+40[Al %]+490[P %]?430??(1) 0.008?Ti*<1.2[C %]??(2), where Ti*=Ti?3.4[N %].

Abstract: Disclosed is a carburized machine part which is free from the problem of decreased strength at edge-shaped parts due to excess introduction of carbon. The machine part is produced by processing a case hardening steel of the alloy composition consisting essentially of, by weight %, C: 0.1-0.3%, Si: 0.5-3.0%, Mn: 0.3-3.0%, P: up to 0.03%, S: up to 0.03%, Cu: 0.01-1.00%, Ni: 0.01-3.00%, Cr: 0.3-1.0%, Al: up to 0.2% and N: up to 0.05% and the balance of Fe and inevitable impurities, and satisfying the following condition: [Si %]+[Ni %]+Cu %]?[Cr %]>0.5 and carburizing by vacuum carburization.

Abstract: The present invention provides a method for manufacturing a hot stamped body, the method including: a hot-rolling step; a coiling step; a cold-rolling step; a continuous annealing step; and a hot stamping step, in which the continuous annealing step includes a heating step of heating the cold-rolled steel sheet to a temperature range of equal to or higher than Ac1° C. and lower than Ac3° C.; a cooling step of cooling the heated cold-rolled steel sheet from the highest heating temperature to 660° C. at a cooling rate of equal to or less than 10° C./s; and a holding step of holding the cooled cold-rolled steel sheet in a temperature range of 550° C. to 660° C. for one minute to 10 minutes.

Abstract: Provided is a steel sheet for a formed member having enhanced ductility, a formed member, and a method for manufacturing the formed member, and more particularly, to a steel sheet for making a formed member having high strength and ductility such as an automotive structural member and a reinforcing member, a formed member, and a method for manufacturing the formed member. The steel sheet for a formed member has enhanced ductility, and includes, by weight %, C: 0.1% to 1.0%, Si+Al: 0.4% to 3.0%, Mn: 0.1% to 5.0%, P: 0.0001% to 0.1%, S: 0.0001% to 0.03%, N: 0.03% or less (but not 0%), and the balance of Fe and inevitable impurities. The formed member having high strength and ductility that can be used for forming an automotive structural member, a reinforcing member, etc. In addition, the formed member can be used for a heat-treatable impact resistant member.

Abstract: An electron-beam welded joint including, by mass %, C: 0.02% to 0.1%, Si: 0.03% to 0.30%, Mn: 1.5% to 2.5%, Ti: 0.005 to 0.015%, N: 0.0020 to 0.0060%, O: 0.0010% to 0.0035%, Nb: 0% to 0.020%, V: 0% to 0.030%, Cr: 0% to 0.50%, Mo: 0% to 0.50%, Cu: 0% to 0.25%, Ni: 0% to 0.50%, B: 0% to 0.0030%, S: limited to 0.010% or less, P: limited to 0.015% or less, Al: limited to 0.004% or less, and a balance consisting of iron and unavoidable impurities, wherein an index value CeEB is 0.49% to 0.60%, a number of oxides having an equivalent circle diameter of 1.0 ?m or more is 20 pieces/mm2 or less, and a number of oxides having an equivalent circle diameter of 0.05 ?m or more and less than 0.5 ?m is 1×103 pieces/mm2 to 1×105 pieces/mm2 at a thickness center portion.

Abstract: A steel having a composition that includes C: 0.05 to 0.15%, Si: 0.2 to 1.2%, Mn: 1.0 to 2.0%, Al: 0.005 to 0.10%, N: 0.006% or less, and at least one selected from Ti: 0.03 to 0.13%, Nb: 0.02 to 0.10%, and V: 0.02 to 0.15% is subjected to rough rolling at a reduction of 80% or more and finish rolling at a finish rolling delivery temperature in the range of 800 to 950° C. The finish rolled sheet is subjected to cooling including cooling the finish rolled sheet from the finish rolling delivery temperature to a cooling end temperature in the range of 550 to 610° C. at an average cooling rate of 25° C./sec. or more and cooling the finish rolled sheet from the cooling end temperature of the previous process to a coiling temperature at an average cooling rate of 100° C./sec. or more.

Abstract: A low Ni and high N austenitic-ferritic stainless steel is disclosed. It includes an austenitic-ferritic stainless steel having high formability and punch stretchability, crevice corrosion resistance, corrosion resistance at welded part, or excellent intergranular corrosion resistance, from a stainless steel structured by mainly austenite phase and ferrite phase, and consisting essentially of 0.2% or less C, 4% or less Si, 12% or less Mn, 0.1% or less P, 0.03% or less S, 15 to 35% Cr, 3% or less Ni, and 0.05 to 0.6% N, by mass, by adjusting the percentage of the austenite phase in a range from 10 to 85%, by volume. Furthermore, it includes an austenitic-ferritic stainless steel having higher formability by adjusting the amount of (C+N) in the austenite phase to a range from 0.16 to 2% by mass.

Abstract: Disclosed herein are iron-based alloys having a microstructure comprising a fine-grained ferritic matrix and having a 60+ Rockwell C surface, wherein the ferritic matrix comprises <10 ?m Nb and W carbide precipitates. Also disclosed are methods of welding comprising forming a crack free hardbanding weld overlay coating with such an iron-based alloy. Also disclosed are methods of designing an alloy capable of forming a crack free hardbanding weld overlay, the methods comprising the steps of determining an amorphous forming epicenter composition, determining a variant composition having a predetermined change in constituent elements from the amorphous forming epicenter composition, and forming and analyzing an alloy having the variant composition.

Abstract: Disclosed herein are iron-based alloys having a structure comprising fine-grained ferritic matrix and having a 60+ Rockwell C surface, wherein the ferritic matrix comprises <10 ?m Nb and W carbide precipitates. Also disclosed are methods of welding comprising forming a crack free hardbanding weld overlay coating with such an iron-based alloy. Also disclosed are methods of designing an alloy capable of forming a crack free hardbanding weld overlay, the methods comprising the step determining an amorphous forming epicenter composition, determining a variant composition having a predetermined change in constituent elements from the amorphous forming epicenter composition, and forming and analyzing an alloy having the variant composition.

Abstract: As to the method for fabricating a member of a vehicle, after a member for the vehicle having high-rigidity of martensite organization is fabricated by a hot stamping forming, the martensite organization is transformed to a ferrite having a low-rigidity partially and improved toughness or to a metal organization heat treated by tempering process through induction heating or secondary heat treatment using laser beam of conduction area, and thereby collision absorption performance is improved by stabilizing the absorption directivity of the collision energy without additional reinforcement.

Abstract: The present invention provides a wire rod with a composition at least including: C: 0.95-1.30 mass %; Si: 0.1-1.5 mass %; Mn: 0.1-1.0 mass %; Al: 0-0.1 mass %; Ti: 0-0.1 mass %; P: 0-0.02 mass %; S: 0-0.02 mass %; N: 10-50 ppm; O: 10-40 ppm; and a balance including Fe and inevitable impurities, wherein 97% or more of an area in a cross-section perpendicular to the longitudinal direction of the wire rod is occupied by a pearlite, and 0.5% or less of an area in a central area in the cross-section and 0.5% or less of an area in a first surface layer area in the cross-section are occupied by a pro-eutectoid cementite.

Abstract: Embodiments of the present disclosure are directed to methods of manufacturing steel tubes that can be used for mining exploration, and rods made by the same. Embodiments of the methods include a quenching of steel tubes from an austenitic temperature prior to a cold drawing, thereby increasing mechanical properties within the steel tube, such as yield strength, impact toughness, hardness, and abrasion resistance. Embodiments of the methods reduce the manufacturing step of quenching and tempering ends of a steel tube to compensate for wall thinning during threading operations. Embodiments of the methods also tighten dimensional tolerances and reduce residual stresses within steel tubes.

Abstract: A strain aging hardening type steel sheet excellent in aging resistance, and manufacturing method thereof, said steel sheet comprises: in mass %, C: 0.0010 to 0.010%; Si: 0.005 to 1.0%; Mn: 0.08 to 1.0%; P: 0.003 to 0.10%; S: 0.0005 to 0.020%; Al: 0.010 to 0.10%; Cr: 0.005 to 0.20%; Mo: 0.005 to 0.20%; Ti: 0.002 to 0.10%; Nb: 0.002 to 0.10%; N: 0.001 to 0.005%; and a balance being composed of Fe and inevitable impurities, in which a ferrite fraction is 98% or more, an average grain diameter of ferrite is 5 to 30 ?m, a minimum value of dislocation density in a portion having a ½ thickness of a sheet thickness and a minimum value of dislocation density in a surface layer portion are each 5×1012/m2 or more, and an average dislocation density falls within a range of 5×1012 to 1×1015/m2.

Abstract: The present invention provides a bake-hardenable high-strength cold-rolled steel sheet having excellent bake hardenability, cold aging resistance, and deep-drawability, and reduced planar anisotropy, containing chemical components in % by mass of: C: 0.0010% to 0.0040%, Si: 0.005% to 0.05%, Mn: 0.1% to 0.8%, P: 0.01% to 0.07%, S: 0.001% to 0.01%, Al: 0.01% to 0.08%, N: 0.0010% to 0.0050%, Nb: 0.002% to 0.020%, and Mo: 0.005% to 0.050%, a value of [Mn %]/[P %] being in the range of 1.6 to 45, where [Mn %] is an amount of Mn and [P %] is an amount of P, an amount of C in solid solution obtained from [C %]?(12/93)×[Nb %] being in the range of 0.0005% to 0.

Abstract: The present disclosure is directed and formulations and methods to provide non-stainless steel alloys having relative high strength and ductility. The alloys may be provided in sheet or pressed form and characterized by their particular alloy chemistries and identifiable crystalline grain size morphology. The alloys are such that they include boride pinning phases. In what is termed a Class 1 Steel the alloys indicate tensile strengths of 630 MPa to 1100 MPa and elongations of 10-40%. Class 2 Steel indicates tensile strengths of 875 MPa to 1590 MPa and elongations of 5-30%. Class 3 Steel indicates tensile strengths of 1000 MPa to 1750 MPa and elongations of 0.5-15%.

Abstract: A thin high strength steel sheet having excellent formability has a composition which includes, by mass %, 0.08 to 0.15% of C, 0.5 to 1.5% of Si, 0.5 to 1.5% of Mn, 0.01 to 0.1% of Al, and 0.005% or less of N to form a hot rolled sheet is conducted.

Abstract: An aspect of the present disclosure is directed to low-alloy steels exhibiting high hardness and an advantageous level of multi-hit ballistic resistance with low or no crack propagation imparting a level of ballistic performance suitable for military armor applications. Various embodiments of the steels according to the present disclosure have hardness in excess of 550 BHN and demonstrate a high level of ballistic penetration resistance relative to conventional military specifications.

Abstract: The present invention provides a steel sheet with chemical components including, by mass%, 0.18-0.35% of C, 1.0%-3.0% of Mn, 0.01%-1.0% of Si, 0.001%-0.02% of P, 0.0005%-0.01% of S, 0.001%-0.01% of N, 0.01%-1.0% of Al, 0.005%-0.2% of Ti, 0.0002%-0.005% of B, and 0.002%-2.0% of Cr, and the balance of Fe and inevitable impurities, wherein: by volume%, a fraction of the ferrite is 50% or more, and a fraction of a non-recrystallized ferrite is 30% or less; and Cr?/CrM is 2 or less, where Cr? is a concentration of Cr subjected to solid solution in iron carbide and CrM is a concentration of Cr subjected to solid solution in a base material, or Mn0/MnM is 10 or less, where Mn0 is a concentration of Mn subjected to solid solution in an iron carbide, and MnM is a concentration of Mn subjected to solid solution in a base material.

Abstract: It is an object of the present invention to provide a high strength cold-rolled steel sheet, which has superior bake hardenability, aging resistance at room temperature and secondary work embrittlement resistance, and a method for manufacturing the same. The steel sheet has a grain size of ASTM No. of 9 or more after annealing, a BH of 30 MPa or more, an AI of 30 MPa or less, and a tensile strength of 340˜390 MPa through appropriate control of solute elements in steel by addition of a small amount of Ti, addition of Al and Mo, and control of manufacturing conditions, and refinement of crystal grains after annealing. The cold-rolled steel sheet and the galvannealed steel sheet produced using the cold-rolled steel sheet have the superior bake hardenability, aging resistance at room temperature, and secondary work embrittlement resistance.

Abstract: A steel material which is suitable for hot press working or hot three-dimensional bending and direct quench and which can be used to manufacture a high-strength formed article with sufficient quench hardening even by short time heating at a low temperature has a chemical composition comprising, in mass percent, C: 0.05-0.35%, Si: at most 0.5%, Mn: 0.5-2.5%, P: at most 0.03%, S: at most 0.01%, sol. Al: at most 0.1%, N: at most 0.01%, and optionally at least one element selected from the group consisting of B: 0.0001-0.005%, Ti: 0.01-0.1%, Cr: 0.18-0.5%, Nb: 0.03-0.1%, Ni: 0.18-1.0%, and Mo: 0.03-0.5% and has a steel structure in which the spheroidization ratio of carbides is 0.60-0.90.

Abstract: A high-strength galvanized steel sheet having excellent formability and crashworthiness, including a component composition containing 0.03% to 0.13% C, 1.0% to 2.0% Si, 2.4% to 3.5% Mn, 0.001% to 0.05% P, 0.0001% to 0.01% S, 0.001% to 0.1% Al, 0.0005% to 0.01% N, and 0.0003% to 0.01% B on a mass basis, the remainder being Fe and unavoidable impurities, and a microstructure containing a tempered martensitic phase and a bainitic phase such that the sum of an area fraction of the tempered martensitic phase and an area fraction of the bainitic phase is 30% or more (the area fraction of the martensitic phase is 30% or more in the absence of the bainitic phase), wherein a distance of closest approach of the tempered martensitic phase is 10 ?m or less and the contents of C, Mn, and B satisfy (1): (% Mn)+1000×(% B)?35 ×(% C) ??(1).

Abstract: A high-strength hot-rolled steel sheet having excellent formability has a composition containing, by mass, 0.04% to 0.1% of C, 0.3% to 1.3% of Si, 0.8% to 1.8% of Mn, 0.03% or less of P, 0.005% or less of S, 0.005% or less of N, 0.005% to 0.1% of Al, and at least one element selected from 0.002% to less than 0.03% of Ti, 0.002% to less than 0.03% of V, and 0.002% to less than 0.02% of Nb, the balance being Fe and incidental impurities. The steel sheet has a microstructure in which the area fraction of ferrite phase in the entire structure is 85% or more, the area fraction of bainite phase in the entire structure is 10% or less, the area fraction of phases other than the ferrite and bainite phases in the entire structure is 5% or less, and the area fraction of acicular ferrite phase in the entire ferrite phase is 30% to less than 80%.

Abstract: An abrasion resistant steel plate which is excellent in toughness and delayed fracture resistance of a multi pass weld and is preferably used in construction machines, industrial machines and the like is provided. To be more specific, the composition of the steel plate contains by mass % 0.20 to 0.30% C, 0.05 to 1.0% Si, 0.40 to 1.2% Mn, 0.010% or less P, 0.005% or less S, 0.40 to 1.5% Cr, 0.005 to 0.025% Nb, 0.05 to 1.0% Mo, 0.005 to 0.03% Ti, 0.1% or less Al, 0.01% or less N, and 0.0003 to 0.0020% B, and further contains one, two or more kinds of components selected from a group consisting of W, Cu, Ni, V, REM, Ca and Mg when necessary, wherein DI* (DI*=33.85×(0.1×C)0.5×(0.7×Si+1)×(3.33×Mn+1)×(0.35×Cu+1)×(0.36×Ni+1)×(2.16×Cr+1)×(3×Mo+1)×(1.75×V+1)×(1.5×W+1)) is 45 to 180, C+Mn/4-Cr/3+10P?0.47, and a base phase of the microstructure is formed of martensite.

Abstract: A high strength hot-rolled steel sheet with a tensile strength of not less than 590 MPa which exhibits excellent bake hardenability and stretch-flangeability has a chemical composition including, in terms of mass %, C at 0.040 to 0.10%, Si at not more than 0.3%, Mn at 1.7 to 2.5%, P at not more than 0.030%, S at not more than 0.005%, Al at not more than 0.1% and N at 0.006 to 0.025%, and microstructure wherein a bainite phase represents not less than 60%, the total of a ferrite phase and a pearlite phase represents not more than 10%, and the bainite phase includes grains among which cementite grains have been precipitated at not less than 1.4×104 grains/mm2 and the cementite grains have an average grain diameter of not more than 1.5 ?m.

Abstract: The present invention provides a method for manufacturing a hot stamped body having a vertical wall, the method including: a hot-rolling step; a coiling step; a cold-rolling step; a continuous annealing step; and a hot stamping step, in which the continuous annealing step includes a heating step of heating the cold-rolled steel sheet to a temperature range of equal to or higher than Ac1° C. and lower than Ac3° C.; a cooling step of cooling the heated cold-rolled steel sheet from the highest heating temperature to 660° C. at a cooling rate of equal to or less than 10° C./s; and a holding step of holding the cooled cold-rolled steel sheet in a temperature range of 550° C. to 660° C. for one minute to 10 minutes.

Abstract: A high-strength steel plate includes the following composition: 0.18 to 0.23 mass % of C; 0.1 to 0.5 mass % of Si; 1.0 to 2.0 mass % of Mn; 0.020 mass % or less of P; 0.010 mass % or less of S; greater than 0.5 mass % and equal to or less than 3.0 mass % of Cu, 0.25 to 2.0 mass % of Ni; 0.003 to 0.10 mass % of Nb; 0.05 to 0.15 mass % of Al; 0.0003 to 0.0030 mass % of B; 0.006 mass % or less of N; and a balance composed of Fe and inevitable impurities. A weld crack sensitivity index Pcm of the high-strength steel plate is calculated by Pcm=[C]+[Si]/30+[Mn]/20+[Cu]/20+[Ni]/60+[Cr]/20+[Mo]/15+[V]/10+5[B], and is 0.39 mass % or less. The Ac3 transformation point is equal to or less than 850° C., the percentage value of a martensite structure is equal to or greater than 90%, the yield strength is equal to or greater than 1300 MPa, and the tensile strength is equal to or greater than 1400 MPa and equal to or less than 1650 MPa.

Abstract: A high strength steel sheet excellent in warm stamp formability and a method for manufacturing the same. The steel has a composition containing, in terms of % by mass, C: 0.01 to 0.2%, Si: 0.5% or lower, Mn: 2% or lower, P: 0.03% or lower, S: 0.01% or lower, Al: 0.07% or lower, and N: 0.01% or lower and further containing one or two or more elements selected from Ti, Nb, V, Mo, W, and B.

Abstract: Hot-rolled steel has a chemical composition containing, by mass%, C: 0.18% or more and 0.29% or less, N: 0.0050% or less, Ti: 0.002% or more and 0.05% or less, B: 0.0005% or more and 0.0050% or less, and appropriately controlled amounts of Si, Mn, P, S, Al, and a tensile strength of 500 MPa or less with a variation in tensile strength of 60 MPa or less throughout a region including the edges in the width direction of the steel sheet, and having excellent cold formability and hardenability.

Abstract: This profiled wire, of NACE grade, made of low-alloy carbon steel intended to be used in the offshore oil exploitation sector, is characterized in that it has the following chemical composition, expressed in percentages by weight of the total mass: 0.75<% C<0.95; 0.30<% Mn<0.85; Cr?0.4%; V?0.16%; Si?1.40% and preferably ?0.15%; and optionally no more than 0.06% Al, no more than 0.1% Ni and no more than 0.

Abstract: A case hardened steel with excellent cold forgeability and excellent impact properties after case hardening processing contains C, Si, Mn, S, Cr, Al, Ti, Nb, B, and N, with the balance being iron and unavoidable impurities. Of precipitates containing Ti and/or Nb, precipitates having a size of not less than 20 ?m2 are at a number density of not more than 1.0/mm2. Of precipitates containing Ti and/or Nb, precipitates having a size of more than 5 ?m2 and less than 20 ?m2 and containing Mn and S are at a number density of more than 0.7/mm2 and not more than 3.0/mm2. The ferrite fraction is more than 77% by area.

Abstract: The present invention provides bearing steel, comprising a chemical composition including by mass %, C: 0.56%?[% C]?0.70%, Si: 0.15%?[% Si]<0.50%, Mn: 0.60%?[% Mn]?1.50%, Cr: 0.50%?[% Cr]?1.10%, Mo: 0.05%?[% Mo]?0.5%, P: [% P]?0.025%, S: [% S]?0.025%, Al: 0.005%?[% Al]?0.500%, O: [% O]?0.0015%, N: 0.0030%?[% N]?0.015%, and remainder as Fe and incidental impurities.

Abstract: The invention relates to a steel plate, the chemical composition of which comprises, the contents being expressed by weight: 0.010%?C?0.20%, 0.06%?Mn?3%, Si?1.5%, 0.005%?Al?1.5%, S?0.030%, P?0.040%, 2.5%?Ti?7.2%, (0.45×Ti)?0.35%?B?(0.45×Ti)+0.70%, and optionally one or more elements chosen from: Ni?1%, Mo?1%, Cr?3%, Nb?0.1%, V?0.1%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting.

Abstract: This high-strength steel sheet includes by mass percentage: 0.05 to 0.4% of C; 0.1 to 2.5% of Si; 1.0 to 3.5% of Mn; 0.001 to 0.03% of P; 0.0001 to 0.01% of S; 0.001 to 2.5% of Al; 0.0001 to 0.01% of N; 0.0001 to 0.008% of O; and a remainder composed of iron and inevitable impurities, wherein a steel sheet structure contains by volume fraction 10 to 50% of a ferrite phase, 10 to 50% of a tempered martensite phase, and a remaining hard phase, wherein a 98% hardness is 1.5 or more times as high as a 2% hardness in a range from ? to ? of a thickness of the steel sheet, wherein a kurtosis K* of the hardness distribution between the 2% hardness and the 98% hardness is ?1.2 to ?0.4, and wherein an average crystal grain size in the steel sheet structure is 10 ?m or less.

Abstract: A steel sheet including C at 0.05 to 0.15%, Si at 0.2 to 1.2%, Mn at 1.0 to 2.0%, P at not more than 0.04%, S at not more than 0.0030%, Al at 0.005 to 0.10%, N at not more than 0.005% and Ti at 0.03 to 0.13%, the balance being Fe and inevitable impurities, includes surface regions having an area fraction of bainite of less than 80% and an area fraction of a ferrite phase with a grain diameter of 2 to 15 ?m of not less than 10%, the surface regions extending from both surfaces of the steel sheet each to a depth of 1.5 to 3.0% relative to a total sheet thickness, as well as an inner region other than the surface regions having an area fraction of a bainite phase of more than 95%, and has a tensile strength of not less than 780 MPa.

Abstract: The steel sheet includes C: 0.04 to 0.12%, Si: 0.5 to 1.2%, Mn: 1.0 to 1.8%, P: not more than 0.03%, S: not more than 0.0030%, Al: 0.005 to 0.20%, N: not more than 0.005% and Ti: 0.03 to 0.13%, the balance being Fe and inevitable impurities, includes a microstructure containing a bainite phase at an area fraction exceeding 95% and having an average grain diameter of not more than 3 ?m, has a difference ?Hv1 of not more than 50 between a Vickers hardness value at 50 ?m from the surface and a Vickers hardness value at ¼ of a sheet thickness, has a difference ?Hv2 of not more than 40 between the Vickers hardness value at ¼ of the sheet thickness and a Vickers hardness value at ½ of the sheet thickness.

Abstract: The present invention provides a wire rod with a composition at least including: C: 0.95-1.30 mass %; Si: 0.1-1.5 mass %; Mn: 0.1-1.0 mass %; Al: 0-0.1 mass %; Ti: 0-0.1 mass %; P: 0-0.02 mass %; S: 0-0.02 mass %; N: 10-50 ppm; O: 10-40 ppm; and a balance including Fe and inevitable impurities, wherein 97% or more of an area in a cross-section perpendicular to the longitudinal direction of the wire rod is occupied by a pearlite, and 0.5% or less of an area in a central area in the cross-section and 0.5% or less of an area in a first surface layer area in the cross-section are occupied by a pro-eutectoid cementite.

Abstract: A hot-rolled steel sheet has an average value of the X-ray random intensity ratio of a {100} <011> to {223} <110> orientation group at least in a sheet thickness central portion that is in a sheet thickness range of ? to ? from a steel sheet surface of 1.0 to 6.0, an X-ray random intensity ratio of a {332} <113> crystal orientation of 1.0 to 5.0, rC which is an r value in a direction perpendicular to a rolling direction of 0.70 to 1.10, and r30 which is an r value in a direction that forms an angle of 30° with respect to the rolling direction of 0.70 to 1.10.

Abstract: Provided is a steel sheet having a tensile strength of 980 MPa or more and exhibiting a high yield ratio and an excellent workability. The steel sheet includes C, Si, Mn, B, at least one of Ti, Nb and V, P, S, Al and N, the content by percentage of each of which is in a specified range. The metal structure thereof includes bainite, and martensite and may include ferrite. The proportion by area of bainite in the entire metal structure is 42 to 85%, that of martensite is 15 to 50%, that of ferrite is 5% or less, and that of entire microstructure of the balance other than bainite, martensite and ferrite is 3% or less thereof. Furthermore, bainite has an average crystal grain diameter of 7 ?m or less.

Abstract: A method for manufacturing a coated part having very high mechanical properties using hot forming techniques. The method includes:—providing an annealed steel strip or blank or pre-shaped part that was coated with a metal or metal alloy before the annealing—if a strip is provided, cutting a blank from the strip before or after the annealing—optionally forming a pre-shaped part from the blank—heating the blank or preshaped part to a temperature of 500° C. at an average heating rate of 16° C./s or more—further heating the blank or pre-shaped part to a temperature between 700 and 1000° C.—hot forming the blank or preshaped part into a hot formed part—hardening the hot formed part. A method for manufacturing a coated steel strip, blank or pre-shaped part, and a coated steel strip, blank or part and a hot formed part.

Abstract: A high carbon steel sheet having superior strength and ductility and a method for manufacturing the same comprising: 0.2 to 1.0 wt % carbon (C), 0 to 3.0 wt % silicon (Si), 0 to 3.0 wt % manganese (Mn), 0 to 3.0 wt % chromium (Cr), 0 to 3.0 wt % nickel (Ni), 0 to 0.5 wt % molybdenum (Mo), 0 to 3.0 wt % aluminum (Al), 0 to 0.01 wt % boron (B), 0 to 0.5 wt % titanium (Ti), and the remainder substantially being iron (Fe) and inevitable impurities. The contents of carbon, manganese, chromium, and nickel satisfy the following Equation 1, and the contents of silicon and aluminum satisfy the following Equation 2: (3.0?2.5×C)wt %?(Mn+Cr+Ni/2)?8.5 wt %—(Equation 1) Si+Al>1.0 wt % (Equation 2).

Abstract: A steel for a carburizing and a carburized steel component having a steel portion and a carburized layer with a thickness of more than 0.4 mm to less than 2 mm which is formed on an outside of the steel portion. A chemical composition of the steel for the carburizing and the steel portion of the carburized steel component satisfies simultaneously equations of a hardness parameter, a hardenability parameter, and an AlN precipitation parameter.

Abstract: A steel for a carburizing and a carburized steel component having a steel portion and a carburized layer with a thickness of more than 0.4 mm to less than 2 mm which is formed on an outside of the steel portion. A chemical composition of the steel for the carburizing and the steel portion of the carburized steel component satisfies simultaneously equations of a hardness parameter, a hardenability parameter, and a TiC precipitation parameter.

Abstract: A high-strength cold rolled steel sheet has excellent formability and crashworthiness and includes, on a mass % basis, C: 0.05 to 0.3%, Si: 0.3 to 2.5%. Mn: 0.5 to 3.5%, P: 0.003 to 0.100%, 5: 0.02% or less, Al: 0.010 to 0.5%, the balance being iron and unavoidable impurities, the high-strength cold rolled steel sheet having a microstructure including 20% or more of ferrite on an area fraction basis, 10 to 60% of tempered martensite on an area fraction basis, 0 to 10% of martensite on an area fraction basis, and 3 to 15% of retained austenite on a volume fraction basis.

Abstract: A predetermined composition is had, when a C content is represented by (C %), in a case of (C %) being not less than 0.35% nor more than 0.65%, a volume fraction of pearlite is 64×(C %)+52% or more, and in a case of (C %) being greater than 0.65% and 0.85% or less, the volume fraction of pearlite is not less than 94% nor more than 100%, and a structure of the other portion is composed of one or two of proeutectoid ferrite and bainite. Further, in a region to a depth of 1.0 mm from a surface, a volume fraction of pearlite block having an aspect ratio of 2.0 or more is not less than 70% nor more than 95%, and a volume fraction of pearlite having an angle between an axial direction and a lamellar direction on a cross section parallel to the axial direction of 40° or less is 60% or more with respect to all pearlite.

Abstract: Described is a high tensile strength hot rolled steel sheet having high strength and formability, and a manufacturing method. It has tensile strength?980 MPa and excellent formability, and specifically identified ranges by mass % of C, Si, Mn, P, S, N, Al, Ti, V, Solute V, and Solute Ti; (ii) microstructure with fine carbides dispersion precipitated therein, the fine carbides containing Ti and V and having the average particle diameter<10 nm, as well as volume ratio with respect to the entire microstructure?0.007; and matrix as ferrite phase having area ratio with respect to the entire microstructure?97%. C, Ti, V, S and N satisfy (1) Ti?0.08+(N/14×48+S/32×48) and (2) 0.8?(Ti/48+V/51)/(C/12)?1.2, where “C”, “Ti”, “V”, “S” and “N” represent contents (mass %) of corresponding elements, respectively.

Abstract: A high-strength galvanized steel sheet has a TS of at least 590 MPa and excellent ductility and stretch flangeability and a method for manufacturing the high-strength galvanized steel sheet. The galvanized steel sheet contains, on the basis of mass percent, C: 0.05% to 0.3%, Si: 0.01% to 2.5%, Mn: 0.5% to 3.5%, P: 0.003% to 0.100% or less, S: 0.02% or less, and Al: 0.010% to 1.5%. The total of Si and Al is 0.5% to 2.5%. The remainder are iron and incidental impurities, contain 20% or more of ferrite phase, 10% or less of martensite phase, and 10% to 60% of tempered martensite, on the basis of area percent, and 3% to 10% of retained austenite phase on the basis of volume fraction. The retained austenite has an average grain size of 2.0 ?m or less.

Abstract: A hot-rolled steel sheet according to the present invention is a steel sheet containing a predetermined components, and satisfying O<S/Ca<0.8, N?14/48×Ti?“0” (zero) %. It is a high-strength hot-rolled steel sheet for a spiral pipe excellent in low-temperature toughness in which a pro-eutectoid ferrite fraction is 3% or more and 20% or less, and the other is a low-temperature transformation phase in a microstructure at a depth of a half thickness of a sheet thickness from a steel sheet surface, a number average crystal grain size of a whole of the microstructure is 2.5 ?m or less, an area average grain size is 9 ?m or less, a standard deviation of the area average grain size is 2.3 ?m or less, and a reflected X-ray intensity ratio {211}/{111} in a {211} direction and in a {111} direction relative to a plane in parallel to the steel sheet surface at the depth of the half thickness of the sheet thickness from the steel sheet surface is 1.1 or more.

Abstract: A hot-stamped steel according to the present invention includes, by mass %, C: 0.20% to 0.35%, Si: 0.1% to 0.5%, the total of at least one selected from Mn and Cr: 1% to 3%, Al: 0.005% to 0.06%, Ti: 0.002% to 0.1%, Nb: 0.002% to 0.1%, O: 0.003% to 0.007%, and a balance of iron and inevitable impurities, wherein P is limited to 0.015% or less, S is limited to 0.01% or less, N is limited to 0.004% or less, the dimensional ratio of the lengths of prior austenite grains in a rolling direction to the lengths of the prior austenite grains in the sheet thickness direction is 1.3 to 2.5, the average grain size of the prior austenite grains is 6 ?m or less, the microstructure includes 98% or more of martensite, and the tensile strength is 1470 MPa or more.

Abstract: The present disclosure is directed and formulations and methods to provide non-stainless steel alloys having relative high strength and ductility. The alloys may be provided in sheet or pressed form and characterized by their particular alloy chemistries and identifiable crystalline grain size morphology. The alloys are such that they include boride pinning phases. In what is termed a Class 1 Steel the alloys indicate tensile strengths of 630 MPa to 1100 MPa and elongations of 10-40%. Class 2 Steel indicates tensile strengths of 875 MPa to 1590 MPa and elongations of 5-30%. Class 3 Steel indicates tensile strengths of 1000 MPa to 1750 MPa and elongations of 0.5-15%.

Abstract: A high strength hot-rolled steel sheet has a composition containing more than 0.035% to 0.055% C, 0.2% or less Si, 0.35% or less Mn, 0.03% or less P, 0.03% or less S, 0.1% or less Al, 0.01% or less N, 0.08% to 0.25% Ti, and 0.0005% to 0.0035% B on a mass basis, solute B being 0.0005% or more, the remainder being Fe and unavoidable impurities; a matrix containing a ferrite phase having an area fraction of more than 95%; a microstructure in which Ti carbides having an average grain size of less than 10 nm are finely precipitated in grains of the ferrite phase and the volume fraction of the Ti carbides is 0.0015 to 0.007; and a tensile strength of 780 MPa or more.