Abstract: This hot-rolled wire rod includes, as a chemical composition, by mass %: C: 0.90% to 1.10%; Si: 0.50% to 0.80%; Mn: 0.10% to 0.70%; Cr: 0.10% to 0.40%; P: 0.020% or less; S: 0.015% or less; N: 0.0060% or less; O: 0.0040% or less; and a remainder consisting of Fe and impurities, in which Formulas (1) and (2) are satisfied by mass %, the structure of the hot-rolled wire rod consists of pearlite in an area ratio of 95.0% or more and a remainder, and TS, which is a tensile strength in unit of MPa, and TS*, which is determined from the C content, the Si content, and the Cr content, satisfy Formula (3), 0.50?[Si]+[Cr]?0.90??(1) 0.40?[Cr]+[Mn]?0.80??(2) ?50<TS?TS*<50??(3) where the TS* is calculated by Formula (3?), TS*=1000×[C]+100×[Si]+125×[Cr]+150??(3?).

Abstract: A nitrided steel part excellent in bending straightening ability and bending fatigue characteristic enabling reduction of size and decrease of weight of parts or enabling demand for high load capacities to be met, using as a material a steel material containing, by mass %, C: 0.2 to 0.6%, Si: 0.05 to 1.5%, Mn: 0.2 to 2.5%, P: 0.025% or less, S: 0.003 to 0.05%, Cr: 0.05 to 0.5%, Al: 0.01 to 0.05%, and N: 0.003 to 0.025%, and having a balance of Fe and impurities, having formed on the steel surface a compound layer of a thickness 3 ?m or less comprising iron, nitrogen, and carbon and a hardened layer formed below the compound layer, and having an effective hardened layer depth of 160 to 410 ?m.

Abstract: A nitrided steel part excellent in pitting resistance and bending fatigue characteristic enabling reduction of size and decrease of weight of parts or enabling demand for high load capacities to be met, using as a material a steel material containing, by mass %, C: 0.05 to 0.25%, Si: 0.05 to 1.5%, Mn: 0.2 to 2.5%, P: 0.025% or less, S: 0.003 to 0.05%, Cr: over 0.5 to 2.0%, Al: 0.01 to 0.05%, and N: 0.003 to 0.025%, having a balance of Fe and impurities, having formed on the steel surface a compound larger of a thickness 3 ?m or less containing iron, nitrogen, and carbon and a hardened layer formed below the compound layer, and having an effective hardened layer depth of 160 to 410 ?m.

Abstract: Provided is a steel wire rod for wire drawing containing, in terms of % by mass, C: from 0.90 to 1.20%, Si: from 0.10 to 1.30%, Mn: from 0.20 to 1.00%, Cr: from 0.20 to 1.30%, Al: from 0.005 to 0.050%, and the balance being composed of Fe and impurities, wherein a content of each N, P, and S, which are contained as the impurities, is N: from 0.0070% or less, P: from 0.030% or less, S: from 0.010% or less, and the steel wire rod having a metallographic structure of which 95% or more by volume ratio is a lamellar pearlite structure, wherein the lamellar pearlite structure has an average lamellar spacing of from 50 to 75 nm, an average length of cementites in the lamellar pearlite structure is 1.0 to 4.0 ?m, and a percentage of a number of cementites having a length of 0.5 ?m or less among the cementites in the lamellar pearlite structure is 20% or less.

Abstract: A wire rod according to an aspect of the present invention includes a chemical composition within a predetermined range; in which an average value of % Mn+2 x % Cr over an entirety of the wire rod is 0.50% to 1.00%; 90% or more of a metallographic structure is pearlite by area fraction, and the area fraction of the cementite is less than 3%; a maximum grain size of TiN is less than 15 ?m; a maximum value of % Mn+2 x % Cr in a region where both a S content and an 0 content are less than 1% in a central portion is 2.0 times or less than the average value of % Mn+2x % Cr over the entirety of the wire rod, and a ratio of the maximum value to a minimum value of % Mn+2x % Cr in a region where both a S content and an 0 content are less than 1% in an outer circumferential portion is 2.0 or less.

Abstract: A steel wire rod according to an aspect of the present invention has a chemical composition in a predetermined range, in which a structure in a central part includes 80 area % to 100 area % of pearlite and a total of 0 area % or more and less than 20 area % of proeutectoid ferrite, proeutectoid cementite, martensite, and bainite; an average lamellar spacing of the pearlite in the central part is 50 nm to 100 nm; an average length of lamellar cementite in the central part is 1.9 ?m or less; an average pearlite block size in the central part is 15.0 ?m to 30.0 ?m; a structure in a surface part includes 70 area % to 100 area % of the pearlite; and an average pearlite block size in the surface part is 0.40 times or more and 0.87 times or less the average pearlite block size in the central part.

Abstract: A steel wire for drawing includes, as a chemical composition, by mass %: C: 0.9% to 1.2%, Si: 0.1% to 1.0%, Mn: 0.2% to 1.0%, and Cr: 0.2% to 0.6%, limits Al, N, P, and S to be predetermined ranges, and includes one or more selected from the group consisting of Mo: 0% to 0.20%, and B: 0% to 0.0030%, a remainder of Fe and impurities; in which a metallographic structure includes pearlite, a volume fraction of the pearlite is 95% or higher, an average lamellar spacing of the pearlite is 50 nm to 75 nm, an average length of cementite in the pearlite is 2.0 ?m to 5.0 ?m, and a ratio of the number of grains of cementite with a length of 0.5 ?m or smaller to the cementite in the pearlite is 20% or lower.

Abstract: Provided is a steel wire rod for wire drawing containing, in terms of % by mass, C: from 0.90 to 1.20%, Si: from 0.10 to 1.30%, Mn: from 0.20 to 1.00%, Cr: from 0.20 to 1.30%, Al: from 0.005 to 0.050%, and the balance being composed of Fe and impurities, wherein a content of each N, P, and S, which are contained as the impurities, is N: from 0.0070% or less, P: from 0.030% or less, S: from 0.010% or less, and the steel wire rod having a metallographic structure of which 95% or more by volume ratio is a lamellar pearlite structure, wherein the lamellar pearlite structure has an average lamellar spacing of from 50 to 75 nm, an average length of cementites in the lamellar pearlite structure is 1.0 to 4.0 ?m, and a percentage of a number of cementites having a length of 0.5 ?m or less among the cementites in the lamellar pearlite structure is 20% or less.

Abstract: A low alloy steel is heated to a temperature ranging from 550 to 620° C., and high KN and low KN value processes are performed for a total process time of A: 1.5 to 10 hours. In the high KN value process, a nitriding potential KNX given by Formula (1): 0.15 to 1.50, the average KNX value KNXave: 0.30 to 0.80, and the process time is X in hours. In the low KN value process, which is performed after the high KN value process, a nitriding potential KNY given by Formula (1): 0.02 to 0.25, the average KNY value KNYave: 0.03 to 0.20, and the process time is Y in hours. Average nitriding potential value KNave determined by Formula (2) ranges from 0.07 to 0.30. KNi=(NH3 partial pressure)/(H2 partial pressure)3/2]??(1) KNave=(X×KNXave+Y×KNYave)/A??(2) where i is X or Y.

Abstract: A nitrided steel part excellent in bending straightening ability and bending fatigue characteristic enabling reduction of size and decrease of weight of parts or enabling demand for high load capacities to be met, using as a material a steel material containing, by mass %, C: 0.2 to 0.6%, Si: 0.05 to 1.5%, Mn: 0.2 to 2.5%, P: 0.025% or less, S: 0.003 to 0.05%, Cr: 0.05 to 0.5%, Al: 0.01 to 0.05%, and N: 0.003 to 0.025%, and having a balance of Fe and impurities, having formed on the steel surface a compound layer of a thickness 3 ?m or less comprising iron, nitrogen, and carbon and a hardened layer formed below the compound layer, and having an effective hardened layer depth of 160 to 410 ?m.

Abstract: A nitrided steel part excellent in pitting resistance and bending fatigue characteristic enabling reduction of size and decrease of weight of parts or enabling demand for high load capacities to be met, using as a material a steel material containing, by mass %, C: 0.05 to 0.25%, Si: 0.05 to 1.5%, Mn: 0.2 to 2.5%, P: 0.025% or less, S: 0.003 to 0.05%, Cr: over 0.5 to 2.0%, Al: 0.01 to 0.05%, and N: 0.003 to 0.025%, having a balance of Fe and impurities, having formed on the steel surface a compound larger of a thickness 3 ?m or less containing iron, nitrogen, and carbon and a hardened layer formed below the compound layer, and having an effective hardened layer depth of 160 to 410 ?m.

Abstract: A steel wire for drawing includes, as a chemical composition, by mass %: C: 0.9% to 1.2%, Si: 0.1% to 1.0%, Mn: 0.2% to 1.0%, and Cr: 0.2% to 0.6%, limits Al, N, P, and S to be predetermined ranges, and includes one or more selected from the group consisting of Mo: 0% to 0.20%, and B: 0% to 0.0030%, a remainder of Fe and impurities; in which a metallographic structure includes pearlite, a volume fraction of the pearlite is 95% or higher, an average lamellar spacing of the pearlite is 50 nm to 75 nm, an average length of cementite in the pearlite is 2.0 ?m to 5.0 ?m, and a ratio of the number of grains of cementite with a length of 0.5 ?m or smaller to the cementite in the pearlite is 20% or lower.

Abstract: A low alloy steel is heated to a temperature ranging from 550 to 620° C., and high KN and low KN value processes are performed for a total process time of A: 1.5 to 10 hours. In the high KN value process, a nitriding potential KNX given by Formula (1): 0.15 to 1.50, the average KNX value KNXave: 0.30 to 0.80, and the process time is X in hours. In the low KN value process, which is performed after the high KN value process, a nitriding potential KNY given by Formula (1): 0.02 to 0.25, the average KNY value KNYave: 0.03 to 0.20, and the process time is Y in hours. Average nitriding potential value KNave determined by Formula (2) ranges from 0.07 to 0.30. KNi=(NH3 partial pressure)/(H2 partial pressure)3/2]??(1) KNave=(X×KNXave+Y×KNYave)/A??(2) where i is X or Y.

Abstract: A nozzle is moved while supplying a photoresist liquid from a slit. A photoresist layer is formed on a film. A resist pattern which covers a portion of the film is formed from the photoresist layer by photolithography. Inspection of the resist pattern is performed. The photolithography includes an exposure which is performed so as to transfer a latent image to the photoresist layer, and a development of the photoresist layer which is performed so as to leave the latent image. The latent image contains a dummy latent image which extends in an unbroken manner parallel to the longitudinal direction of the slit. The resist pattern contains a dummy resist formed correspondingly to the dummy latent image. The inspection of the resist pattern includes the detection of the presence or non-presence of a cut in the dummy resist in the longitudinal direction.

Abstract: A nozzle is moved while supplying a photoresist liquid from a slit. A photoresist layer is formed on a film. A resist pattern which covers a portion of the film is formed from the photoresist layer by photolithography. Inspection of the resist pattern is performed. The photolithography includes an exposure which is performed so as to transfer a latent image to the photoresist layer, and a development of the photoresist layer which is performed so as to leave the latent image. The latent image contains a dummy latent image which extends in an unbroken manner parallel to the longitudinal direction of the slit. The resist pattern contains a dummy resist formed correspondingly to the dummy latent image. The inspection of the resist pattern includes the detection of the presence or non-presence of a cut in the dummy resist in the longitudinal direction.

Abstract: Steel tubes for bearing element parts according to the present invention, wherein the specific compositions are limited and an accumulation intensity of {211} face along with an impact property at ambient temperature in the longitudinal direction of steel tube are specified, can be provided as a source material for bearing element parts, which have excellent machinability and fatigue life in rolling contact, being incorporated without adding a free-cutting element specifically nor without reducing productivity since the spheroidizing for the same annealing duration with that of conventional spheroidizing treatment can be applied. Accordingly, by applying a manufacturing method or a cutting-machining method according to the present invention, bearing element parts such as races, rollers and shafts can be produced with less cost and efficiently.

Abstract: Steel tubes for bearing element parts according to the present invention, wherein the specific compositions are limited and an accumulation intensity of {211} face along with an impact property at ambient temperature in the longitudinal direction of steel tube are specified, can be provided as a source material for bearing element parts, which have excellent machinability and fatigue life in rolling contact, being incorporated without adding a free-cutting element specifically nor without reducing productivity since the spheroidizing for the same annealing duration with that of conventional spheroidizing treatment can be applied. Accordingly, by applying a manufacturing method or a cutting-machining method according to the present invention, bearing element parts such as races, rollers and shafts can be produced with less cost and efficiently.