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:
A steel wire rod which is a material of steel wires includes, as a metallographic structure, by area %, 95% to 100% of a pearlite, wherein an average pearlite block size at a central portion of the steel wire rod is 1 μm to 25 μm, an average pearlite block size at a surface layer portion of the steel wire rod is 1 μm to 20 μm, and, when a minimum lamellar spacing of the pearlite at the central portion of the steel wire rod is S in unit of nm and when a distance from a peripheral surface of the steel wire rod to a center is r in unit of mm, S
Abstract:
The present invention inexpensively provides with high productivity and good yield a steel rod superior in drawability and a steel wire superior in twistability using the same as a material, that is, draws a high strength steel rod superior in ductility where the chemical components contain C: 0.80 to 1.20%, Si: 0.1 to 1.5%, Mn: 0.1 to 1.0%, Al: 0.01% or less, Ti: 0.01% or less, one or both of W: 0.005 to 0.2% and Mo: 0.003 to 0.2%, N: 10 to 30 ppm, B: 4 to 30 ppm (of which, solute B is 3 ppm or more), and O: 10 to 40 ppm, which has a balance of Fe and unavoidable impurities, has an area percentage of pearlite structures of 97% or more, has a balance of non-pearlite structures, and has a total of the area percentage of the non-pearlite structures and the area percentage of the coarse pearlite structures of 15% or less, to obtain high strength steel wire superior in ductility having a tensile strength of 3600 MPa or more and a number density of voids of lengths of 5 μm or more at the center of 100/mm2 or less.
Abstract:
A steel wire rod which is a material of steel wires includes, as a metallographic structure, by area %, 95% to 100% of a pearlite, wherein an average pearlite block size at a central portion of the steel wire rod is 1 μm to 25 μm, an average pearlite block size at a surface layer portion of the steel wire rod is 1 μm to 20 μm, and, when a minimum lamellar spacing of the pearlite at the central portion of the steel wire rod is S in unit of nm and when a distance from a peripheral surface of the steel wire rod to a center is r in unit of mm, S
Abstract:
High performance high carbon wire with refined inclusions after wire rolling, extremely low wire breakage rates at the time of drawing even in tough applications, and excellent in fatigue characteristics after wire drawing, characterized by having a predetermined composition of ingredients and in that the number ratio of inclusions satisfying (% SiO2)=40 to 95%, (% CaO)=0.5 to 30%, (% Al2O3)=0.5 to 30%, (% MgO)=0.5 to 20%, and (% MnO)=0.5 to 10% and further satisfying (% Na)=0.2 to 7% and (% F)=0.17 to 8% (below, referred to as “inclusions covered due to composition”) in the oxide-based nonmetallic inclusions of a short axis of 0.5 μm or more, a long axis of 1.0 μm or more, and a circle equivalent diameter (area converted to diameter) of 1 μm or more which are seen in the L direction cross-section of the wire (below, referred to as “inclusions covered due to size”), that is, the number of inclusions covered due to composition/number of inclusions covered due to size×100, is 80% or more.
Abstract:
The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is hot rolled, the hot-rolled steel is coiled in a specified temperature range, and the coiled steel is subjected to patenting at a predetermined cooling rate, thereby affording a high-carbon steel wire excellent in workability. It is high-strength steel wire excellent in drawability comprising a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and having a pearlite block size of not less than 20 μm and not greater than 45 μm. The invention also provides a high-carbon steel wire excellent in ductility, which is manufactured by subjecting the wire rod to intermediate patenting and cold drawing and has a tensile strength of 2800 MPa or greater.
Abstract:
A wire rod which is mainly composed of pearlite and has an area fraction of 5% or less of a non-pearlite structure composed of pro-eutectoid ferrite, degenerate-pearlite or bainite in a section, or has an area fraction of 10% or less of a non-pearlite structure in a portion from the surface to a depth of 100 μm.
Abstract:
The invention provides a steel material with satisfactory hydrogen embrittlement resistance, and particularly it relates to high-strength steel with satisfactory hydrogen embrittlement resistance and a strength of 1200 MPa or greater, as well as a process for production thereof. At least one simple or compound deposit of oxides, carbides or nitrides as hydrogen trap sites which trap hydrogen with a specific trap energy is added to steel, where the mean sizes, number densities, and length-to-thickness ratios (aspect ratio) are in specific ranges. By applying the specific steel components and production process it is possible to obtain high-strength steel with excellent hydrogen embrittlement resistance.
Abstract:
[Problems] To provide a compound which is useful as an NMDA receptor antagonist.[Means for Solution] The present inventors have studied a compound having an NMDA receptor antagonistic action, and confirmed that the fused indane compound of the present invention has an excellent NMDA receptor antagonistic action, thereby completed the present invention. The fused indane compound of the present invention has an excellent NMDA receptor antagonistic action and can be used as a prophylactic and/or therapeutic agent for Alzheimer's disease, cerebrovascular dementia, Parkinson's disease, intractable depression, attention deficit hyperactivity disorder, migraines, or the like.
Abstract:
The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is hot rolled, the hot-rolled steel is coiled in a specified temperature range, and the coiled steel is subjected to patenting at a predetermined cooling rate, thereby affording a high-carbon steel wire excellent in workability. It is high-strength steel wire excellent in drawability comprising a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and having a pearlite block size of not less than 20 μm and not greater than 45 μm. The invention also provides a high-carbon steel wire excellent in ductility, which is manufactured by subjecting the wire rod to intermediate patenting and cold drawing and has a tensile strength of 2800 MPa or greater.