Abstract: A submerged arc welding wire is provided that has a composition including, by mass %, C: 0.20 to 0.80%, Si: 0.15 to 0.90%, Mn: 15.0 to 30.0%, P: 0.030% or less, S: 0.030% or less, Cr: 6.0 to 15.0%, and N: 0.120% or less, the balance being Fe and incidental impurities. Where necessary, the wire may contain one or two selected from Ni and Mo, may further contain one, or two or more selected from V, Ti, and Nb, and may additionally contain one, or two or more selected from Cu, Al, Ca, and REM.

Abstract: Provided is a cold rolling method by which the occurrence of wrinkles during cold rolling can be prevented without having to modify a mill. A cold rolling method of rolling a steel sheet in multiple rolling passes using a cold mill, the method including when the steel sheet unit tension N1 during steady-state rolling exceeds the reference unit tension N0 in a specific rolling pass in which the target sheet thickness t0 on an exit side of the rolling pass is less than or equal to a reference sheet thickness, controlling the steel sheet unit tension N2 in an initial stage of rolling on an entry side of the specific rolling pass to be less than the reference unit tension N0 and less than the steel sheet unit tension N1 during the steady-state rolling, the reference unit tension N0 is calculated by the formula (1): N0=(150/9)t0+27.1.

Abstract: Provided is a hot-dip galvanized steel sheet having both high strength and good workability, as well as excellent coating quality. The chemical composition of the base steel sheet is set within a specified range, the steel microstructure of the base steel sheet is a complex structure of ferrite, martensite and bainite, oxygen is present as oxides in the surface layer of the base steel sheet in an amount of 0.05 g/m2 or more and 0.50 g/m2 or less per surface, and the hot-dip galvanized layer contains Fe in an amount of 0.40 mass % or more.

Abstract: A laser welding method and a laser welding apparatus used for this method are proposed. In the laser welding method, when Si-containing steel sheets are passed through a continuous processing line, a tail end of a preceding steel sheet and a leading end of a succeeding steel sheet are placed in contact with each other on a line entry side, and while a filler wire is supplied to a contact part, laser is applied and a filler is melted and solidified to weld the Si-containing steel sheets together. This method includes injecting a shielding gas containing a He gas or an Ar gas and further containing at least one type selected from a CO2 gas and an N2 gas by 10 vol % or higher and 30 vol % or lower in total to a front surface and a back surface of a part being welded.

Abstract: A method for detecting abnormal vibration of a rolling mill including a collecting step of collecting vibration data of the rolling mill, a frequency analysis step of generating first analysis data indicative of vibration intensities at respective frequencies by performing frequency analysis of the vibration data, a data conversion step of converting the first analysis data into second analysis data indicative of vibration intensities at respective intervals on the basis of a rolling speed, and a map generation step of generating a vibration map in which a plurality of the second analysis data are arranged in time series.

Abstract: It is provided a surface-treated steel sheet that can be produced without using hexavalent chromium and has excellent film wet adhesion and coating secondary adhesion as well as high film corrosion resistance and coating corrosion resistance. It is a surface-treated steel sheet having: a steel sheet; a metallic Cr layer disposed on at least one surface of the steel sheet; and a Cr oxide layer disposed on the metallic Cr layer, and the surface-treated steel sheet has a water contact angle of 50° or less and a total atomic ratio of K, Na, Mg, and Ca adsorbed on the surface to Cr of 5% or less.

Abstract: Provided is an iron-based alloy sintered body having a tensile strength of 800 MPa or more, excellent machinability, a microstructure with an average Vickers hardness of 300 Hv or more and 900 Hv or less and a standard deviation of Vickers hardness of 200 Hv or less, and an average pore circularity of 0.30 or more.

Abstract: An electric resistance welded steel pipe and a method for manufacturing the same are provided. The present invention relates to an electric resistance welded steel pipe including a base metal zone and a weld. In the electric resistance welded steel pipe, steel microstructures at a wall-thickness-wise middle of the base metal zone are steel microstructures in which a bcc phase is present in a volume fraction greater than or equal to 80%, an average grain size is less than or equal to 15.0 ?m, and an A value, defined by a predetermined equation, is 0.55 or greater and 0.85 or less; a yield ratio in a pipe axis direction is less than or equal to 90%; and a Charpy absorbed energy at ?40° C. of the base metal zone is greater than or equal to 100 J.

Abstract: A method of calculating residual stress includes: measuring strain of a deformed portion of the metal sheet in a deformation process of plastically deforming the metal sheet and acquiring a strain history of the measured strain; calculating a stress increment of the deformed portion in the deformation process according to a material constitutive model using an acquired strain increment calculated from the acquired strain history and an assumed strain increment calculated, by assuming a deformation state of the deformed portion, from strain other than the strain from which the strain history is acquired, and sequentially updating stress from a start to an end of deformation of the deformed portion using the calculated stress increment; and determining, as residual stress of the deformed portion, the stress of the deformed portion at the end of the deformation in the deformation process among the sequentially updated stresses.

Abstract: Provided is a steel sheet having excellent workability while ensuring excellent strength. The steel sheet comprises: a predetermined chemical composition; and a steel microstructure that contains ferrite: 45% to 90%, martensite: 5% to 30%, bainite: 1% to 25%, and retained austenite: 3% or more and in which [Mn]M/[Mn] is 1.00 to 1.15 and [Mn]M/[Mn]F is 1.00 to 1.30, wherein TS×El is 16000 MPa·% or more.

Abstract: Provided is a steel pipe or tube for hydrogen gas that has both excellent hydrogen embrittlement resistance and high productivity and can be used very suitably as parts of pressure vessels for hydrogen gas. The steel pipe or tube for hydrogen gas having a finish-polished inner surface, in which the inclination angle of a polishing trace present on the inner surface with respect to a circumferential direction of the steel pipe or tube for hydrogen gas is 0° to 30°.

Abstract: Provided is a method for stably producing a grain-oriented electrical steel sheet with excellent magnetic properties by effectively purifying inhibitors. The method for producing a grain-oriented electrical steel sheet includes using a steel slab containing a predetermined amount of at least one of Ti, Zr, Hf, V, Nb, and Ta, and applying an annealing separator, in which 1 part by mass to 10 parts by mass of a metal compound is added with respect to 100 parts by mass of MgO, on the steel sheet surface with a ratio of particles with a particle size of 1 ?m or more in the metal compound being 0.0010 particles/?m2 or less.

Abstract: A high-strength galvanized steel sheet is disclosed which has a specified chemical composition, has a steel microstructure including, in terms of area fraction, 35% or more and 80% or less of ferrite, 0.1% or more and less than 5.0% of as-quenched martensite, 3.0% or more and 35% or less of tempered martensite, and 8% or more of retained austenite, in which an average grain diameter of the ferrite is 6 ?m or less, in which an average grain diameter of the retained austenite is 3 ?m or less, in which a value calculated by dividing an average Mn content (mass %) in the retained austenite by an average Mn content (mass %) in the ferrite is 1.5 or more.

Abstract: A trigger condition determination method for a time series signal determines a trigger condition for cutting out a monitored section being a target for abnormality diagnosis, from a monitored signal being a time series signal indicating a condition of a monitored facility in the abnormality diagnosis for the monitored facility, and includes: collecting signal groups including one or more monitored signals and a trigger candidate signal; cutting out the monitored section of the monitored signal; generating a learning model specifying a start time point of the cut-out monitored section, generating label data, and using one or more trigger candidate signals at each time point as an input and using the label data at each time point as an output, by using machine learning; and determining the trigger condition by using the learning model, for the monitored signal for which the abnormality diagnosis is performed.

Abstract: A high-pressure hydrogen container includes: a cylinder body; and a lid member that closes an end portion of the cylinder body. The cylinder body includes: a joining portion that fixes the lid member; a cylinder portion that forms an outer shell of a storage portion; and a sealing surface formed at an inner surface of the cylinder body. At least H<K is satisfied, where an area of the sealing surface which the sealing portion abuts is an abutting area, H is a thickness from the abutting area to an outer surface of the cylinder body, part of the cylinder body in which a stress greater than or equal to a predetermined stress ? is generated is a stress generation portion, and L is a distance between the abutting area and the stress generation portion.

Abstract: A position detection apparatus for a seam portion and a heating portion of a welded steel pipe, the position detection apparatus includes: a light source configured to irradiate the seam portion and the heating portion with light in a first wavelength range; an imaging unit having a plurality of different channels and configured to capture an image of each of the seam portion and the heating portion irradiated with the light by the light source; and an image processing unit configured to process the image captured by the imaging unit and to detect the position of each of the seam portion and the heating portion, wherein the imaging unit includes: a first channel capable of receiving the light in the first wavelength range; and a second channel capable of receiving light in a second wavelength range corresponding to radiation light from the heating portion.

Abstract: An object is to provide a lifting-magnet attachment magnetic pole unit, a lifting magnet, a steel material conveying method, and a steel plate manufacturing method with which only one or a desired pieces of steel materials can be held. The present invention is a lifting-magnet attachment magnetic pole unit for a lifting magnet used to lift and convey a steel material with magnetic force. The lifting-magnet attachment magnetic pole unit includes a first split magnetic pole that is in contact with an iron core of the lifting magnet and has a branched structure, and a second split magnetic pole that is in contact with a yoke of the lifting magnet and has a branched structure. The first and second split magnetic poles are alternately arranged.

Abstract: Provided is a grain-oriented electrical steel sheet comprising a magnetic flux density B8 of 1.92 T or more, wherein a ratio Wa/Wb of a film thickness Wa of a forsterite film on a strain-introduced surface to a film thickness Wb of a forsterite film on a non-strain-introduced surface is 0.5 or more, an average width of a magnetic domain discontinuous portion on the non-strain-introduced surface is 1.00 time or more of an average width of a magnetic domain discontinuous portion on the strain-introduced surface, the average width of the magnetic domain discontinuous portion on the non-strain-introduced surface is 400 ?m or less, and compressive stress exists in a rolling direction in a range from a surface of the steel sheet that is the strain-introduced surface to at least 2 ?m in a sheet thickness direction.

Abstract: Provided is a stainless steel foil for a catalyst support of an exhaust gas purifier excellent in both diffusion bonding resistance and brazeability and also excellent in oxidation resistance at high temperatures. The stainless steel foil for a catalyst support of an exhaust gas purifier comprises: a predetermined chemical composition; a parameter Sa defined in ISO 25178 of 0.50 ?m to 3.00 ?m; and a parameter Str defined in ISO 25178 of 0.20 to 1.00.

Abstract: To provide an Fe-based electroplated steel sheet that not only has excellent chemical convertibility or excellent coating appearance when subjected to hot-dip galvanizing, but also has excellent resistance to cracking in resistance welding. Disclosed is an Fe-based plated steel sheet including: a cold-rolled steel sheet having a chemical composition containing Si in an amount of 0.1 mass % or more and 3.0 mass % or less; and an Fe-based electroplating layer formed on one or both surfaces of the cold-rolled steel sheet with a coating weight per surface of 1.0 g/m2 or more, in which a thickness of an internal oxidation layer is 2.00 ?m or less, and an average value of C concentration in a range of 10 ?m to 20 ?m in a thickness direction from the surface of the Fe-based electroplating layer is 0.10 mass % or less.