Abstract: A ferritic steel sheet wherein a mean value of X-ray random intensity ratios of a group of {100}<011> to {223}<110> orientations is 3.0 or more and a mean value of X-ray random intensity ratios of three crystal orientations of {554}<225>, {111}<112>, and {111}<110> is 3.5 or less and further at least one of the r values in a rolling direction and a direction at a right angle of that is 0.7 or less.

Abstract: A steel material and a steel pipe made by using the same are provided which are to be used in severe oil well environments. Such a highly tough oil well steel pipe can be produced by rolling the base material, quenching the rolling product from the austenite region and tempering the same so that the relationship between the content of Mo [Mo] in the carbides precipitated at austenite grain boundaries and the austenite grain size (according to ASTM E 112) can be defined by the formula (a) given below. In this manner, steel pipes suited for use even under oil well environments becoming more and more severe can be produced while satisfying the requirements that the cost should be rationalized, the productivity improved and energy saved.

Abstract: A weldable structural steel product having fine complex precipitates of TiN and MnS is provided which contains, in terms of percent by weight, 0.03 to 0.17% C, 0.01 to 0.05% Si, 1.0 to 2.5% Mn, 0.05 to 0.2% Ti, 0.0005 to 0.1% Al, 0.008 to 0.030% N, 0.0003 to 0.01% B, 0.001 to 0.2% W, at most 0.03% P, 0.003 to 0.05% S, at most 0.005% O, and balance Fe and incidental impurities while satisfying conditions of 1.2?Ti/N?2.5, 10?N/B?40, 2.5?Al/N?7, 6.5?(Ti+2Al+4B)/N?14, and 220?Mn/S?400. The steel has a microstructure consisting essentially of a complex structure of ferrite and pearlite having a grain size of 20 ?m or less.

Abstract: The present invention presents a high tensile strength cold rolled steel sheet having excellent formability, impact resistance and strain age hardening characteristics, and the production thereof. As a specific means, a slab having a composition which contains, by mass %, 0.15% or less of C, 0.02% or less of Al, and 0.0050 to 0.0250% of N at N/Al of 0.3 or higher, and has N in a solid solution state at 0.0010% or more, is first hot rolled at the finish rolling delivery-side temperature of 800° C. or above, and is subsequently coiled at the coiling temperature of 750° C. or below to prepare a hot rolled plate. Then, after cold rolling, the hot rolled plate is continuously cooled at a temperature from the recrystallization temperature to 900° C. at a holding time of 10 to 120 seconds, and is cooled by primary cooling in which the hot rolled plate is cooled to 500° C. or below at a cooling rate of 10 to 300° C.

Abstract: A mainly bainitic steel having the following composition in weight percent: carbon 0.6-1.1; silicon 1.5 to 2.0; manganese 1.8 to 4.0; chromium 1.2 to 1.4; nickel 0-3; molybdenum 0.2 to 0.5; vanadium 0.1 to 0.2, balance iron save for incidental impurities.

Abstract: In order to manufacture a steel pipe for an air bag which can cope with increase in the pressure of gas blown into an air bag and decreases in the wall thickness of an accumulator, a steel having a composition, mass %, of: C: 0.05-0.20%, Si: 0.1-1.0%, Mn: 0.20-2.0%, P: at most 0.025%, S: at most 0.010%, Cr: 0.05-1.0%, Al: at most 0.10%, if necessary at least one of Mo: at most 0.50%, Ni: at most 1.5%, Cu: at most 0.5%, V: at most 0.2%, Ti: at most 0.1%, Nb: at most 0.1%, and B: at most 0.005%, and also if necessary, at least one of Ca: at most 0.01%, Mg: at most 0.01%, and REM (rare earth elements): at most 0.01%, and a remainder of Fe and impurities is used to produce a steel pipe, and the pipe is then subjected to cold working to predetermined dimensions, then to heating to a temperature of at least the Ac1 transformation temperature followed by quenching, and then to tempering at a temperature no higher than the Ac1 transformation temperature.

Abstract: A bar or wire product for use in cold forging, characterized in that it comprises a steel having the chemical composition, in mass %: C: 0.1 to 0.6%, Si: 0.01 to 0.5%, Mn: 0.2 to 1.7%, S: 0.001 to 0.15%, Al: 0.015 to 0.05%, N: 0.003 to 0.025%, P: 0.035% or less, O: 0.003% or less and balance: Fe and inevitable impurities, and it has, in the region from the surface thereof to the depth of the radius thereof×0.15, a structure wherein ferrite accounts for 10 area % or less and the balance is substantially one or more of martensite, bainite and pearlite, and the average hardness in the region from the depth of the radius thereof×0.5 to the center thereof is less than that of the surface layer thereof by 20 or more of HV; and a method for producing the bar or wire product.

Abstract: The present invention is a high strength steel pipe excellent in formability in hydroforming and similar forming methods, characterized by: containing, in mass, C of 0.0005 to 0.30%, Si of 0.001 to 2.0%, Mn of 0.01 to 3.0% and appropriate amounts of other elements if necessary, with the balance consisting of Fe and unavoidable impurities; and an average for the ratios of the X-ray strength in the orientation component group of {110}<110> to {111}<110> to random X-ray diffraction strength on a plane at the wall thickness center being 2.0 or more and/or a ratio of the X-ray strength in the orientation component of {110}<110> to random X-ray diffraction strength on the plane at the wall thickness center being 3.0 or more.

Abstract: The invention concerns a steel article, which consists of an alloy having a chemical composition, which contains in weight-%: 1.2 to 2.5 C; 0.8 to 2.0 Si, which partly can be replaced by aluminium, which may exist in an amount of max 1.0%; 0.1 to 1.5 Mn; 0.5 to 1.5 Cr; 1.2 to 5.0 (V+Nb/2), however max 1.0 Nb; balance iron and impurities in normal amounts, and having a microstructure which contains 4 to 12 volume-% of MC-carbides. The steel article can be used for manufacturing of cold-work tools, particularly pilger rolls for cold rolling of tubes. The invention also relates to a method of manufacturing the article.

Abstract: Method for the production of a part of a rolling bearing, such as a ring for a ball bearing. The starting material used is a grade of steel containing 0.90 1.00% C; at most 0.15% Si; 0.25-0.45% Mn; at most 0.0015% P; at most 0.010% S; 1.30-1.50% Cr; at most 0.15% Ni; 0.20-0.23% Mo; at most 0.20-0.23% Cu; at most 20 ppm Ti; at most 8 ppm O. Before subjecting this grade of steel to a quenching and tempering treatment, the shaped item is subjected to plastic deformation in the hot or cold state. The mechanical properties and in particular the anticipated life under severe stress improve as a result.

Abstract: A non-heat treated seamless steel tube has a composition consisting of, by weight, C: 0.10 to 0.25%, Si: 0.05 to 1.0%, Mn: 0.5 to 2.5%, P: not more than 0.03%, S: not more than 0.05%, Cr: 0.5 to 2.0%, V: 0.03 to 0.3%, Al 0.003 to 0.10%, N: 0.001 to 0.

Abstract: A heat-resisting steel comprising 0.15-0.30 wt. % C, 0.05-0.3 wt. % Si, 0.01-0.7 wt. % Mn, 1.8-2.5 wt. % Cr, 0.15-0.23 wt. % V, 1.5-2.5 wt. % W, 0.01-0.02 wt. % Ti, 0.01-0.08 wt. % Nb, 0.005-0.03 wt. % N, 0.001-0.015 wt. % B, and Fe and unavoidable impurities as the remainder; a heat-resisting steel comprising 0.15-0.30 wt. % C, 0.05-0.3 wt. % Si, 0.01-0.7 wt. % Mn, 1.8-2.5 wt. % Cr, 0.15-0.23 wt. % V, 1.5-2.5 wt. % W, 0.3-0.8 wt. % Mo, 0.01-0.02 wt. % Ti, 0.01-0.08 wt. % Nb, 0.005-0.03 wt. % N, 0.001-0.015 wt. % B, and Fe and unavoidable impurities as the remainder; and a heat-resisting steel that is obtained by subjecting one of the above heat-resisting steels to a heat treatment comprising the step of oil-cooling the heat-resisting steel to a temperature of 300° C. or lower. These heat-resisting steels are excellent in both high-temperature strength and impact properties.

Abstract: A heat resistant steel can be produced at a low cost and has an excellent high temperature strength. A high-strength heat-resistant steel is provided which comprises carbon in an amount of 0.06 to 0.15% by weight, silicon in an amount of 1.5% by weight or less, manganese in an amount of 1.5% by weight or less, vanadium in an amount of 0.05 to 0.3% by weight, chromium in an amount of 0.8% by weight or less, molybdenum in an amount of 0.8% by weight or less, at least one selected from niobium, titanium, tantalum, hafnium, and zirconium in an amount of 0.01 to 0.2% by weight, nitrogen in an amount of 20 to 200 ppm, and the balance being iron and unavoidable impurities, and the high-strength heat-resistant steel comprising a bainite structure.

Abstract: A high speed tool steel, which is high in impact value and free from variations in tool performance, comprising, by mass %, of: 0.4≦C≧0.9; S1≦1.0; Mn≦1.0; 4≦Cr≧6; 1.5-6 in total of either or both of W and Mo in the form of (1/2 W+Mo) wherein W≦3; 0.5-3 in total of either or both of V and Nb in the form of (V+Nb); wherein carbides dispersed in the matrix of the tool steel have an average grain size of ≦0.5 &mgr;m and a dispersion density of particles of the carbides is of ≧80×103 particles/mm2.

Abstract: A grinding ball having a 55 to 65 Rockwell C hardened outer shell of tempered martensite is adapted for use in heavy duty grinding environments. The ball is stress relieved to stabilize the ball against break up and/or spalling.

Abstract: Disclosed herein is a high-strength high-carbon steel wire which, owing to its high strength as well as good ductility, is excellent in resistance to strain aging embrittlement and longitudinal cracking. The steel wire is characterized by having a chemical composition (in mass %) including C: 0.75-1.20%, Si: 0.1-1.5%, Mn: 0.3-1.2%, P: no more than 0.02%, S: no more than 0.02%, Al: no more than 0.005%, and N: no more than 0.008%, with the remainder being Fe and inevitable impurities. The steel wire is further characterized by having worked pearlite structure containing lamellar cementite in amorphous form, a diameter (D) ranging from 0.15 to 0.4 mm, a metal lubricating film as the surface layer whose main phase is composed of at least one of Cu, Ni, and Zn or an alloy thereof, and tensile strength no lower than (3500×D−0.145) MPa and no higher than (3500×D−0.145+87×[C]−5) MPa, where [C] denotes C content in %.

Abstract: A method for providing a steel product having a surface hardness of between about 360 Bhn and 420 Bhn is provided. The method includes steps of providing a steel product from a steel product comprising at least about 96 wt. % iron and between about 0.24 wt. % and about 0.30 wt. % carbon, heating the steel product to at least its austentizing temperature, quenching to below its martinsite finish temperature, and tempering the steel product at a temperature of at least about 800° F. Steel products prepared by this method are described.

Abstract: A steel alloy, particularly adapted for the manufacture of railway wheels is provided. Such alloy comprises essentially, in weight percentage, carbon 0.67-0.77, manganese 0.70-0.85, silicon 0.65-0.85, phosphorus less than 0.025, sulfur less than 0.025, chromium 0.18-0.25, molybdenum 0.08-0.12, with the balance essentially iron. Another lower carbon alloy comprises essentially, in weight percentage, carbon 0.16-0.45, manganese 0.90-1.10, silicon 0.50-0.70, phosphorous less than 0.035, sulfur less than 0.035, nickel 1.0-1.5, chromium 0.40-0.60 and molybdenum 0.40-0.60.

Abstract: A hot-working steel article, e.g., tool, comprising a material which comprises, in % by weight, 0.451 to 0.598 C, 0.11 to 0.29 Si, 0.11 to 0.39 Mn, 4.2 to 4.98 Cr, 2.81 to 3.29 Mo, 0.41 to 0.69 V, with the balance iron, contaminants and accompanying elements, as well as an alloy and a process for making said article.

Abstract: The present invention provides a rolling bearing having high wear resistance at high temperature and with reduced manufacturing cost. At least one of an inner ring, an outer ring and rolling elements is formed of the following steel material into a predetermined shape, then applied with hardening and tempering at a temperature of 240° C. or higher or 350° C. or lower to make the Vickers hardness (Hv) on the raceway surface and/or rolling surface to 720 or more. The steel material contains, as the alloy ingredient, 0.8% by weight or more and 1.2% by weight or less of C, 0.5% by weight or more and 2.5% by weight or less of Si, 0.7% by weight or more and 1.5% by weight or less of Cr, 0.8% by weight or more and 2.0% by weight or less of Mo and 0.3% by weight or more and 1.2% by weight or less of Mn, with a ratio of Mo to Cr (Mo/Cr: weight ratio) of 1.1 or more.

Abstract: A cold work steel has the following chemical composition in weight-%: 1.25-1.75% (C+N), however at least 0.5 % C 0.1-1.5% Si 0.1-1.5% Mn 4.0-5.5% Cr 2.5-4.5% (Mo+W/2), however max. 0.5% W 3.0-4.5% (V+Nb/2), however max. 0.5% Nb max 0.3% S balance iron and unavoidable impurities, and a microstructure which in the hardened and tempered condition of the steel contains 6-13 vol-% of vanadium-rich MX-carbides, -nitrides and/or carbonitrides which are evenly distributed in the matrix of the steel, where X is carbon and/or nitrogen, at least 90 vol-% of said carbides, nitrides and/or carbonitrides having an equivalent diameter, Deq, which is smaller than 3.0 &mgr;m; and totally max. 1 vol-% of other, possibly existing carbides, nitrides or carbonitrides.

Abstract: A high strength steel alloy for use in manufacturing railway car components. The alloy has a chemical composition that meets the industry required specifications for B grade steel and exhibits better mechanical properties, such as higher yield and tensile strengths. Secondary benefits of the inventive steel alloy include enhanced weldability and improved fatigue resistance.

Abstract: The invention provides a high-carbon steel pipe having superior cold workability and induction hardenability, and a method of producing the steel pipe. The method comprises the steps of heating or soaking a base steel pipe having a composition containing C: 0.3 to 0.8%, Si: not more than 2%, and Mn: not more than 3%, and then carrying out reducing rolling on the base steel pipe at least in the temperature range of (Ac1, transformation point −50° C.) to Ac1, transformation point with an accumulated reduction in diameter of not less than 30%. A structure in which the grain size of cementite is not greater than 1.0 &mgr;m is obtained, thus resulting in improved cold workability and induction hardenability.

Abstract: A cobalt-free martensitic steel exhibiting good response to hardening and resistance to softening at high temperatures, the steel containing sub-micron and nano-structural precipitates and intermetallic compounds of silicon, nickel, aluminum, copper and manganese.

Abstract: A superhigh-strength dual-phase steel sheet containing ferritic microstructure and a martensitic microstructure—containing composite-phase steel sheet containing: C: 0.08-0.20% (mass% here and hereinafter), Si: 0.5% or less (inclusive of 0%) Mn: 3.0% or less (exclusive of 0%) P: 0.02% or less (inclusive of 0%) S: 0.02% or less (inclusive of 0%), and Al: 0.001-0.15%, and further containing Mo: 0.05-1.5%, and Cr: 0.05-1.5%, and which satisfying that: the average Vickers hardness of the ferritic microstructure is 150 Hv or more and the average Vickers hardness of the martensitic microstructure is 500 Hv or more, the superhigh-strength dual-phase steel sheets being of excellent fatigue characteristic in a spot welded joint.

Abstract: An iron-based corrosion resistant and wear resistant alloy. The alloy can comprise (in weight percent) 0.005-0.5% boron, 1.2-1.8% carbon, 0.7-1.5% vanadium, 7-11% chromium, 1-3.5% niobium, 6-11% molybdenum, and the balance including iron and incidental impurities. Alternatively, the Nb content can be replaced or combined with Ti, Zr, Hf and/or Ta such that 1%<(Ti+Zr+Nb+Hf+Ta)≦3.5. The alloy has improved hot hardness and high temperature compressive strength and is suitable for use in elevated temperature applications such as in diesel valve seat inserts.

Abstract: This invention provides a steel sheet for a mask frame which maintains a tension-type color CRT shadow mask under tension. The steel sheet has a steel composition consisting essentially of, in mass %, C: 0.03-0.30%, Si: at most 0.30%, Mn: 0.05-1.5%, P: at most 0.05%, S: at most 0.02%, Mo: 0.02-0.50%, V: 0.02-0.20%, Al: at most 0.10%, N: 0.0040-0.0200%, optionally one or two or more of Cu: at most 1.0%, Ni: at most 1.0%, Cr: at most 2.0%, W: at most 1.0%, B: at most 0.003%, Ti: at most 0.030%, and Nb: at most 0.030%, and a balance of iron and unavoidable impurities, with Al≦(7.0)N, and having a metal structure in which the ferrite grain size is at most 15 micrometers and the ferrite volume ratio is at most 90%. The steel sheet is manufactured by hot rolling of a slab having the above-described steel composition under the conditions of a finishing temperature of 820-950° C. and a coiling temperature of 400-700° C.

Abstract: An ultra-high strength cold rolled steel sheet having a tensile strength of 880 to 1170 MPa, that consists essentially of 0.01 to 0.07% C, 0.3% or less Si, 0.1% or less P, 0.01% or less S, 0.01 to 0.1% sol.Al, 0.0050% or less N, 1.6 to 2.5% of the sum of at least one element selected from the group consisting of Mn, Cr, and Mo, by mass, and a balance of Fe, and that has an inner zone deeper than 10 &mgr;m from the surface of the steel sheet being substantially a martensitic single phase structure. Since the steel sheet has a hole expansion ratio of 75% or more, specified by the Standard of Japan Iron and Steel Federation, JFST1001-1996, the steel sheet has a tensile strength in a range of from 880 to 1170 MPa, and an excellent mechanically joining property, and is suitable for fabricating automobile seat frames.

Abstract: Chain parts and other steel articles are provided with hard, wear-resistant carbide coatings by tumbling them in a heated retort with a particulate mix which includes a source of vanadium and/or niobium. The steel substrate comprises a steel having at least 0.2% carbon, preferably 0.7-1.2%. Where the chromium content of the steel is 4-12%, preferably 4-8%, the chemical deposition process includes drawing a small amount of chromium from the steel substrate into the vanadium or niobium carbide coating, where it is distributed substantially homogeneously, helping to provide adhesion strength to the coating.

Abstract: The present invention provides a steel sheet having a chemical composition comprising 0.15% or less C, 2.0% or less Si, 3.0% or less Mn, P, S, Al and N in adjusted amounts, from 0.5 to 3.0% Cu, or one or more of Cr, Mo and W in a total amount of 2.0% or less, and having a composite structure comprising ferrite and martensite having an area ratio of 2% or more. The steel sheet is in the form of a high-strength hot-rolled steel sheet, a high-strength cold-rolled steel sheet, or a hot-dip galvanized steel sheet. There is thus available a steel sheet excellent in press-formability and in strain age hardening property as represented by a &Dgr;TS of 80 MPa or more.

Abstract: Disclosed is a corrosion resistant steel having good machinability with sufficient corrosion resistance in the ordinary indoor circumstances and suitable for manufacturing shafts of various small motors and OA-machines. The steel comprises, by weight %, C: 0.005-0.200%, P: up to 0.05%, Cu: up to 2.0%, Ni: up to 2.0%, Cr: 2.0-9.0%, one or both of Ti and Zr: in such an amount as [Ti %]+0.52[Zr %]: 0.03-1.20%, one or both of S: 0.01-0.50% and Se: 0.01-0.40%, N: up to 0.050% and O: up to 0.030%, the balance being Fe and inevitable impurities. The steel is characterized by the inclusion therein, which are Ti-based, Zr-based or Ti-Zr-based compound or compounds containing C and one or both of S and Se.

Abstract: The present invention relates to a high strength hot rolled steel sheet containing 0.15% or less C, 0.02 to 0.35% Ti, and 0.05 to 0.7% Mo by weight percentage and consisting essentially of a matrix of ferrite structure single phase and fine precipitates with a grain size of smaller than 10 nm dispersed in the matrix, for example, a high strength hot rolled steel sheet which consists essentially of 0.06% or less C, 0.5% or less Si, 0.5 to 2.0% Mn, 0.06% or less P, 0.005% or less S, 0.1% or less Al, 0.006% or less N, 0.02 to 0.10% Ti, 0.05 to 0.6% Mo by weight percentage, and the balance being Fe, wherein fine precipitates with a grain size of smaller than 10 nm are dispersed in a matrix of ferrite structure single phase at a number per unit volume of 5×104/&mgr;m3 or higher. This steel sheet, which has tensile strength of not lower than 550 MPa, high elongation and excellent stretch flangeability, is suitable for intricately shaped automotive chassis parts such as a suspension arm.

Abstract: Disclosed is a steel alloy that includes as alloying ingredients carbon, silicon, manganese, aluminum, and oxygen. In accordance with this embodiment of the disclosed invention, carbon is present in an amount ranging from 0.40 to 0.77 wt. %; silicon is present in an amount ranging from 0.40 to 1.20 wt. %; manganese is present in an amount ranging from 0.40 to 1.20 wt. %, aluminum is present in an amount ranging from 0.003 to 0.060 wt. %; and oxygen is present in an amount ranging up to 0.0030 wt. %. Also disclosed is a railway wheel that comprises a hub, a rim, and a connecting plate. In accordance with this embodiment of the disclosed invention, at least the rim, and preferably the entire railway wheel, is composed of the disclosed steel composition.

Abstract: The present invention relates to a high strength steel sheet consisting essentially of 0.04 to 0.1% C, 0.5% or less Si, 0.5 to 2% Mn, 0.05% or less P, 0.005% or less 0, 0.005% or less S, by weight, having 10 &mgr;m or less of average ferritic grain size, and 20 mm/mm2 or less of generation frequency A, which generation frequency A is defined as the total length of a banded secondary phase structure observed per 1 mm2 of steel sheet cross section along the rolling direction thereof. The steel sheet is manufactured by, for example, a method comprising the steps of: hot-rolling a continuously cast slab having the composition described above at temperatures of Ar3 transformation point or above directly or after reheating thereof; and cooling the hot-rolled steel sheet within 2 seconds down to the temperatures of from 600 to 750° C. at cooling speeds of from 100 to 2,000° C./sec, followed by coiling the cooled steel sheet at temperatures of from 450 to 650° C.

Abstract: There are provided a high-hardness prehardened steel for cold working having excellent machinability containing, by mass, not less than 0.3% but less than 0.5% C, 0.7 to 2.0% Si, and 0.08 to 0.25% S, a die for cold working which is fabricated by cutting this prehardened steel at a cutting speed not less than 50 m/min. This steel is hardened and tempered to have a hardness not less than 50 HRC. Preferably, this steel consists, by mass, not less than 0.3% but less than 0.5% C, 0.7 to 2.0% Si, 0.1 to 2.0% Mn, 0.08 to 0.25% S, 0.5 to 15.0% Cr, at least one selected from the group consisting of W and Mo an amount of which one is not more than 3.5% in total in terms of (Mo+1/2W), not more than 4.0% V, not more than 0.15% N, and the balance Fe and incidental impurities.

Abstract: A superhigh-strength dual-phase steel sheet containing ferritic microstructure and a martensitic microstructure—containing composite-phase steel sheet containing:

Abstract: The method for manufacturing steel sheet comprises the steps of: rough-rolling to form a sheet bar; finish-rolling the sheet bar to form a steel strip; applying primary cooling and secondary cooling to the finish-rolled steel strip; and coiling the secondary-cooled steel strip. The primary cooling is conducted at cooling speeds of 120° C./sec or more down to the temperatures of from 500 to 800° C. The secondary cooling is conducted at cooling speeds of less than 60° C./sec.

Abstract: There is provided a steel sheet which can simultaneously achieves the following objects: high strength is obtained by quenching with reliability; and excellent ductility is ensured, and further which is excellent in corrosion resistance, plating properties, and spot weldability. The steel sheet is so configured as to satisfy the following composition requirements: on a mass basis, C: 0.11 to 0.22%, Mn: 0.1 to less than 0.5%, Cr and/or Mo: a total amount of 0.1 to 0.5%, and B: 0.0005 to 0.005%, where C: the content of C (% by mass), Cr: the content of Cr (% by mass), and Mo: the content of Mo (% by mass), wherein T≧0.19 where T=C+(Cr+Mo)/5.

Abstract: The invention concerns a steel material which consists of a steel having the following chemical composition in weigh-%: 1.0-1.9 C, 0.5-2.0 Si, 0.1-1.5 Mn, 4.0-5.5 Cr, 2.5-4.0 (Mo+W/2), however max 1.0 W, 2.0-4.5 (V+Nb/2), however max 1.0. Nb, balance iron and impurities in normal amounts in the form of residual elements from the manufacturing of the steel, and with a microstructure, which in the hardened and tempered condition of the steel contains 5-12 vol-% MC-carbides, at least about 80 vol-% of the carbides having a size which is larger than 3 &mgr;m but smaller than 25 &mgr;m preferably smaller than 20 &mgr;m, and, prior to tempering, 0.50-0.70 weight-% carbon, which is dissolved in the martensite in the hardened condition of the steel. The material is intended for cold work tools, in the first place for homogenous rolls for cold rolling of meta, strips.

Abstract: The present invention provides a steel pipe excellent in formability during hydraulic forming and the like and a method to produce the same, and more specifically: a steel pipe excellent in formability having an r-value of 1.4 or larger in the axial direction of the steel pipe, and the property that the average of the ratios of the X-ray intensity in the orientation component group of {110}<110> to {332}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 3.5 or larger, and/or the ratio of the X-ray intensity in the orientation component of {110}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 5.

Abstract: A steel material and a steel pipe made by using the same are provided which are to be used in severe oil well environments. Such a highly tough oil well steel pipe can be produced by rolling the base material, quenching the rolling product from the austenite region and tempering the same so that the relationship between the content of Mo [Mo] in the carbides precipitated at austenite grain boundaries and the austenite grain size (according to ASTM E 112) can be defined by the formula (a) given below. In this manner, steel pipes suited for use even under oil well environments becoming more and more severe can be produced while satisfying the requirements that the cost should be rationalized, the productivity improved and energy saved.

Abstract: A method for providing a steel product having a surface hardness of between about 360 Bhn and 420 Bhn is provided. The method includes steps of providing a steel product from a steel product comprising at least about 96 wt. % iron and between about 0.24 wt. % and about 0.30 wt. % carbon, heating the steel product to at least its austentizing temperature, quenching to below its martinsite finish temperature, and tempering the steel product at a temperature of at least about 800° F. Steel products prepared by this method are described.

Abstract: The present invention provides a high strength bolt superior in delayed fracture resistant property having a bolt tensile strength of 1200 N/mm2 or more and a steel material for the same.

Abstract: The invention relates to a quench-and-temper steel alloy for use in casing for oil and gas wells wherein such casing is exposed to low pH environments. The steel alloy has a carbon range by weight of 0.15% to 0.35%, a manganese range by weight of 0.60% to 1.10%, a molybdenum range by weight of 0.15% to 0.65%, and a sulphur range by weight of less than 0.002%. The steel alloy has a quench-and-temper micro-structure and features precipitated spheroidal molybdenum carbides in manganese- and carbon-rich bands. The steel alloy also has, by weight, a chromium range of less than 0.50%, an aluminum range of less than or equal to 0.08% and a calcium range of less than or equal to 0.0045%.

Abstract: The invention relates to a valve body produced by powder metallurgical methods that exhibits high thermal and wear resistance and has the following composition by weight:

Abstract: A compound structure steel sheet excellent in burring workability made of a steel containing, by mass, 0.01 to 0.3% of C, 0.01 to 2% of Si, 0.05 to 3% of Mn, 0.1% or less of P, 0.01% or less of S, and 0.005 to 1% or Al, and having the microstructure being a compound structure having ferrite as the main phase and martensite or retained austenite mainly as the second phase, the quotient of the volume percentage of the second phase divided by the average grain size of the second phase being 3 or more and 12 or less, and the quotient of the average hardness of the second phase divided by the average hardness of the ferrite being 1.5 or more and 7 or less; or a compound structure steel sheet excellent in burring workability made of a steel containing, by mass, 0.01 to 0.3% of C, 0.01 to 2% of Si, 0.05 to 3% of Mn, 0.1% or less of P, 0.01% or less of S, and 0.

Abstract: A steel for forming a high strength steel sheet contains, in mass %, C: at most 0.04%, Si: at most 0.4%, Mn: 0.5-3.0%, P: at most 0.15%, S: at most 0.03%, Al: at most 0.50%, N: at most 0.01%, and Mo: 0.01-1.0%. Steel sheet formed from the steel is suitable for use as automotive panels.

Abstract: A high bearing pressure-resistant member used as a rolling element forming part of a toroidal continuously variable transmission for an automotive vehicle. The high bearing pressure-resistant member is formed of a mechanical structural steel containing Cr. The mechanical structural steel includes a matrix having at least one of martensite structure and bainite structure. The matrix contains carbide having a mean particle size of 3 &mgr;m or less, dispersed and precipitated in form of at least one of generally spheres and pseudo-spheres.

Abstract: To provide a high-strength steel having a desired strength (800 N/mm2 or higher) for screws and bolts of a large diameter (M8 or larger) that also have a tapping ability, and a high-strength screw made from such a steel. The steel comprises (by % mass) C: 0.05 to 0.20, Si: 0.20 or less (not including 0), Mn: 0.5 to 2.0, P: 0.015 or less, S: 0.015 or less, sol. Al: 0.020 to 0.080, N: 0.0060 or less, Cr: more than 0.80 to 2.0 and the balance being iron and unavoidable impurities.

Abstract: Hot-rolled steel with very high elasticity limit and mechanical resistance usable in particular for auto parts production, characterized by the following composition by weight: 0.08%<carbon<0.16% 1%<manganese<2% 0.02%<aluminum<0.1% silicon<0.5% phosphorus<0.03% sulfur<0.01% vanadium<0.3% chromium<1% nitrogen<0.015% molybdenum<0.6%.