Abstract: An age-hardenable steel having a composition consisting of: C: 0.05 to 0.20%, Si: 0.01 to 0.50%, Mn: 1.5 to 2.5%, S: 0.005 to 0.08%, Cr: more than 0.50% and not more than 1.6%, Al: 0.005 to 0.05%, V: 0.25 to 0.50%, Mo: 0 to 1.0%, Cu: 0 to 0.3%, Ni: 0 to 0.3%, Ca: 0 to 0.005%, and Bi: 0 to 0.4%, the balance being Fe and impurities. Within the impurities, P?0.03%, Ti<0.005%, and N<0.0080%, and [C+0.3Mn+0.25Cr+0.6Mo?0.68], [C+0.1Si+0.2Mn+0.15Cr+0.35V+0.2Mo?1.05], and [?4.5C+Mn+Cr?3.5V?0.8Mo?0.12]. The steel has hardness before aging of not more than 310 HV. After aging, the fatigue strength is not less than 480 MPa and absorbed energy at 20° C. is not less than 12 J.

Abstract: Age hardenable steel is low in hardness after hot forging, providing a machine part with the desired fatigue strength and yield strength by aging treatment, and high in toughness after aging treatment, comprising C: 0.09 to 0.20%, Si: 0.01 to 0.40%, Mn: 1.5 to 2.5%, S: 0.001 to 0.045%, Cr: over 1.00% to 2.00%, Al: 0.001 to 0.060%, V: 0.22 to 0.55%, N: over 0.0080 to 0.0170%, and a balance of Fe and impurities, where an area rate of bainite structures is 80% or more, an effective V ratio (amount of dissolved V/total amount of V) is 0.9 or more, a P and Ti in the impurities is P: 0.03% or less and Ti: less than 0.005%, and the chemical composition is one where the following F1 is 1.00 or less and the F2 is 0.30 or more: F1=C+0.1×Si+0.2×Mn+0.15×Cr+0.35×V F2=?4.5×C+Mn+Cr?3.

Abstract: Rolled steel bar for hot forging consisting, by mass percent, of C: 0.25-0.50%, Si: 0.40-1.0%, Mn: 1.0-1.6%, S: 0.005-0.035%, Al: 0.005-0.050%, V: 0.10-0.30%, N: 0.005-0.030% with the balance being Fe and impurities, i.e., P: 0.035% or less and O: 0.0030% or less, wherein Fn1=C+Si/10+Mn/5+5Cr/22+1.65V?5S/7 is 0.90 to 1.20. The predicted maximum width of nonmetallic inclusions at the time when a cumulative distribution function obtained by extreme value statistical processing by taking the width of nonmetallic inclusion in an R1/2 part of a longitudinal cross section of the steel bar as W (mm) is 99.99% is 100 ?m or narrower. The number density of sulfides each having a circle-equivalent diameter of 0.3 to 1.0 ?m observed per unit area of the R1/2 part of a transverse cross section of the steel bar is 500 pieces/mm2 or higher.

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 rolled steel bar for hot forging consisting, by mass percent, of C: 0.25-0.50%, Si: 0.40-1.0%, Mn: 1.0-1.6%, S: 0.005-0.035%, Al: 0.005-0.050%, V: 0.10-0.30%, and N: 0.005-0.030%, and the balance of Fe and impurities, i.e., P: 0.035% or less and O: 0.0030% or less, wherein Fn1=C+Si/10+Mn/5+5Cr/22+1.65V?5S/7 is 0.90 to 1.20. The predicted maximum width of nonmetallic inclusions at the time when a cumulative distribution function obtained by extreme value statistical processing by taking the width of nonmetallic inclusion in an R1/2 part of a longitudinal cross section of the steel bar as W (?m) is 99.99% is 100 ?m or narrower. The number density of sulfides each having a circle-equivalent diameter of 0.3 to 1.0 ?m observed per unit area of the R1/2 part of a transverse cross section of the steel bar is 500 pieces/mm2 or higher.

Abstract: A rolled steel bar for hot forging consisting, by mass percent, of C: 0.25-0.50%, Si: 0.40-1.0%, Mn: 1.0-1.6%, S: 0.005-0.035%, Al: 0.005-0.050%, V: 0.10-0.30%, and N: 0.005-0.030%, and the balance of Fe and impurities, i.e., P: 0.035% or less and O: 0.0030% or less, wherein Fn1=C+Si/10+Mn/5+5Cr/22+1.65V?5S/7 is 0.90 to 1.20. The predicted maximum width of nonmetallic inclusions at the time when a cumulative distribution function obtained by extreme value statistical processing by taking the width of nonmetallic inclusion in an R1/2 part of a longitudinal cross section of the steel bar as W (mm) is 99.99% is 100 mm or narrower. The number density of sulfides each having a circle-equivalent diameter of 0.3 to 1.0 mm observed per unit area of the R1/2 part of a transverse cross section of the steel bar is 500 pieces/mm2 or higher.

Abstract: Age hardening steel excellent in machinability before aging treatment and excellent in fatigue characteristics, toughness, and low cycle fatigue characteristics after aging treatment, that is, age hardening steel containing predetermined amounts of C, Si, Mn, S, Cr, Al, V, Nb, Ca, and REM, limiting contents of P, Ti, and N to predetermined amounts or less, having a balance of Fe and impurities, having an area ratio of bainite structures of 70% or more, and, furthermore, having a chemical composition where F1 expressed by C+0.3×Mn+0.25×Cr is 0.68 or more, F2 expressed by C+0.1×Si+0.2×Mn+0.15×Cr+0.35×V is 0.85 or less, F3 expressed by ?4.5×C+Mn+Cr?3.5×V is 0.00 or more, and F4 expressed by 10×Ca+REM is 0.012 to 0.08, is provided. Note that, the symbols of elements in the formulas showing F1 to F4 mean the contents by mass % of those elements.

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 steel bar has a composition consisting, by mass percent, of C: 0.27 to 0.37%, Si: 0.30 to 0.75%, Mn: 1.00 to 1.45%, S: 0.008% or more and less than 0.030%, Cr: 0.05 to 0.30%, Al: 0.005 to 0.050%, V: 0.200 to 0.320%, and N: 0.0080 to 0.0200%, the balance being Fe and impurities. The contents of P, Ti and O in the impurities are, by mass percent, P: 0.030% or less, Ti: 0.0040% or less, and O: 0.0020% or less. Y1 expressed by the formula <1> is 1.05 to 1.18. Y1=C+(1/10)Si+(1/5)Mn+(5/22)Cr+1.65V?(5/7)S??<1>. C, Si, Mn, Cr, V, and S in the formula represent mass percent of the elements. A hot-forged part having a tensile strength of 900 MPa or higher and a transverse endurance ratio of 0.47 can be obtained by the rolled steel bar.

Abstract: An age-hardenable steel having a composition consisting of: C: 0.05 to 0.20%, Si: 0.01 to 0.50%, Mn: 1.5 to 2.5%, S: 0.005 to 0.08%, Cr: more than 0.50% and not more than 1.6%, Al: 0.005 to 0.05%, V: 0.25 to 0.50%, Mo: 0 to 1.0%, Cu: 0 to 0.3%, Ni: 0 to 0.3%, Ca: 0 to 0.005%, and Bi: 0 to 0.4%, the balance being Fe and impurities. Within the impurities, P?0.03%, Ti<0.005%, and N<0.0080%, and [C+0.3Mn+0.25Cr+0.6Mo?0.68], [C+0.1Si+0.2Mn+0.15Cr+0.35V+0.2Mo?1.05], and [?4.5C+Mn+Cr?3.5V?0.8Mo?0.12]. The steel has hardness before aging of not more than 310 HV. After aging, the fatigue strength is not less than 480 MPa and absorbed energy at 20° C. is not less than 12 J.

Abstract: An age-hardenable steel consists of: C: 0.05 to 0.20%, Si: 0.01 to 0.50%, Mn: 1.5 to 2.5%, S: 0.005 to 0.08%, Cr: 0.03 to 0.50%, Al: 0.005 to 0.05%, V: 0.25 to 0.50%, Mo: 0 to 1.0%, Cu: 0 to 0.3%, Ni: 0 to 0.3%, Ca: 0 to 0.005%, and Bi: 0 to 0.4%, the balance being Fe and impurities. Within impurities, P £ 0.03%, Ti<0.005%, and N<0.0080%, and [C+0.3Mn+0.25Cr+0.6Mo3 0.68], [C+0.1Si+0.2Mn+0.15Cr+0.35V+0.2Mo £ 0.85], and [?4.5C+Mn+Cr?3.5V?0.8Mo3 0.00]. The hardness before aging is not more than 290 HV, a quantity of hardening by aging being not less than 25 HV, fatigue strength is not less than 350 MPa, and absorbed energy at 20° C. after aging is not less than 16 J.

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: A rolled steel bar for hot forging consisting, by mass percent, of C: 0.25-0.50%, Si: 0.40-1.0%, Mn: 1.0-1.6%, S: 0.005-0.035%, Al: 0.005-0.050%, V: 0.10-0.30%, and N: 0.005-0.030%, and the balance of Fe and impurities, i.e., P: 0.035% or less and O: 0.0030% or less, wherein Fn1=C+Si/10+Mn/5+5Cr/22+1.65V?5S/7 is 0.90 to 1.20. The predicted maximum width of nonmetallic inclusions at the time when a cumulative distribution function obtained by extreme value statistical processing by taking the width of nonmetallic inclusion in an R1/2 part of a longitudinal cross section of the steel bar as W (mm) is 99.99% is 100 mm or narrower. The number density of sulfides each having a circle-equivalent diameter of 0.3 to 1.0 mm observed per unit area of the R1/2 part of a transverse cross section of the steel bar is 500 pieces/mm2 or higher.

Abstract: A rolled steel bar has a composition consisting, by mass percent, of C: 0.27 to 0.37%, Si: 0.30 to 0.75%, Mn: 1.00 to 1.45%, S: 0.008% or more and less than 0.030%, Cr: 0.05 to 0.30%, Al: 0.005 to 0.050%, V: 0.200 to 0.320%, and N: 0.0080 to 0.0200%, the balance being Fe and impurities. The contents of P, Ti and O in the impurities are, by mass percent, P: 0.030% or less, Ti: 0.0040% or less, and O: 0.0020% or less. Y1 expressed by the formula <1> is 1.05 to 1.18. Y1=C+(1/10)Si+(1/5)Mn+(5/22)Cr+1.65V?(5/7)S ??<1>. C, Si, Mn, Cr, V, and S in the formula represent mass percent of the elements. A hot-forged part having a tensile strength of 900 MPa or higher and a transverse endurance ratio of 0.47 can be obtained by the rolled steel bar.

Abstract: A method of processing data packets having multiple fields by a router includes the steps of receiving a packet; calculating separate check values for each of the packet fields; combining the separately calculated check values; masking the combined check values with a predetermined packet check value; and then comparing the masked, calculated check value with an Access Control List (ACL) entry check value. Only if the calculated check value matches the ACL entry check value is the packet data compared with corresponding fields from the corresponding ACL entry.