Provided is a free-cutting steel that, despites not containing Pb, has machinability by cutting higher than or equal to that of a low carbon sulfur-lead composite free-cutting steel. A free-cutting steel comprises: a chemical composition that contains, in mass %, C: less than 0.09%, Mn: 0.50% to 1.50%, S: 0.250% to 0.600%, O: more than 0.010% and 0.050% or less, and Cr: 0.50% to 1.50%, with a balance consisting of Fe and inevitable impurities, and in which a A value defined by the following formula (1) is 6.0 to 18.0, and a steel microstructure in which at least 500 particles/mm.sup.2 of sulfide of less than 1 μm in equivalent circle diameter and at least 2000 particles/mm.sup.2 of sulfide of 1 μm to 5 μm in equivalent circle diameter are distributed.

A chemical composition of a base metal of a non-oriented electrical steel sheet contains, by mass %, C: 0.0050% or less, Si: 3.8% to 5.0%, Mn: exceeding 0.2% and less than 2.0%, P: 0.030% or less, S: 0.0030% or less, Al: 0.005% or more and less than 0.050%, N: 0.0005% to 0.0030%, Ti: less than 0.0050%, Nb: less than 0.0050%, Zr: less than 0.0050%, V: less than 0.0050%, Cu: less than 0.20%, Ni: less than 0.50%, Sn: 0% to 0.10%, Sb: 0% to 0.10%, a remainder: Fe and impurities. [Si+0.5×Mn≥4.3] is satisfied and the average grain size of the base metal is in a range of 10 to 80 μm.

A non-oriented electrical steel sheet has a predetermined chemical composition. The chemical composition satisfies (2×[Mn]+2.5×[Ni]+[Cu])−([Si]+2×[sol.Al]+4×[P])≥1.50%. In a case where Ahkl-uvw represents the area ratio of crystal grains in an {hkl}<uvw> orientation to the entire visual field when a plane at a depth of ½ of a sheet thickness from a surface parallel to a rolled surface is measured by SEM-EBSD, A411-011 is 15.0% or more, and the average grain size is 50 μm to 150 μm.

Provided herein is a stainless steel seamless pipe for oil country tubular goods. A method for manufacturing such a stainless steel seamless pipe is also provided. The stainless steel seamless pipe has: a composition that contains, in mass %, C: 0.10% or less, Si: 0.5% or less, Mn: 0.05 to 0.50%, P: 0.030% or less, S: 0.005% or less, O: 0.0040% or less, Ni: 3.0 to 8.0%, Cr: 10.0 to 14.0%, Mo: 0.5 to 2.8%, Al: 0.1% or less, V: 0.005 to 0.2%, N: 0.10% or less, Cu: 0.01 to 1.0%, Co: 0.01 to 1.0%, and Ca: 0.0005 to 0.0030%, and in which the balance is Fe and incidental impurities; a microstructure containing at most 20 non-metallic inclusions having a predetermined composition ratio of CaO and Al.sub.2O.sub.3 and a major axis of 5 μm or more per 100 mm.sup.2; and a yield stress of 655 MPa or more.

A non oriented electrical steel sheet includes, as a chemical composition, by mass %, 1.0% or more and 5.0% or less of Si, wherein a sheet thickness is 0.10 mm or more and 0.35 mm or less, an average grain size is 30 μm or more and 200 μm or less, an X value defined by X=(2×B.sub.50L+B.sub.50C)/(3×I.sub.S) is 0.800 or more, and an iron loss W.sub.10/1k is 80 W/kg or less.

The present invention has as its object the provision of a coated steel member and coated steel sheet excellent in hydrogen embrittlement resistance in a corrosive environment and methods for manufacturing the same. The coated steel member of the present invention is provided on its surface with an Al—Fe-based coating containing Cu and one or more of Mo, Ni, Mn, and Cr in a total by mass % of 0.12% or more by heating, cooling, and manufacturing a coated steel sheet having a layer containing Cu on its surface under predetermined conditions.

A steel sheet with a tensile strength (TS) of 1180 MPa or more, a member, and a method for producing them. In a region of the steel sheet within 4.9 μm in the thickness direction, a region with a Si concentration not more than one-third of the Si concentration in the chemical composition of the steel sheet and with a Mn concentration not more than one-third of the Mn concentration in the chemical composition of the steel sheet has a thickness of 1.0 μm or more. The lowest Si concentration L.sub.Si and the lowest Mn concentration L.sub.Mn in the region within 4.9 μm in the thickness direction from the surface of the steel sheet and a Si concentration T.sub.Si and a Mn concentration T.sub.Mn at a quarter thickness position of the steel sheet satisfy the following formula (1):

L.sub.Si+L.sub.Mn≤(T.sub.Si+T.sub.Mn)/4  (1).

A steel near-net-shape material having high fatigue strength and high tensile strength is provided. The steel near-net-shape material has a chemical composition containing, in mass %, C: 0.03 to 0.25%, Si: 0.02 to 0.50%, Mn: more than 0.70 to 2.50%, P: 0.035% or less, S: 0.050% or less, Al: 0.005 to 0.050%, V: more than 0.10 to 0.40%, and N: 0.003 to 0.030%. The steel near-net-shape material is composed of polygonal ferrite having an area fraction of 20 to 90% and a hard phase having an area fraction of 10 to 80%, and satisfies Formula (1). A diffusible hydrogen content of the steel near-net-shape material when charged with hydrogen by a cathodic hydrogen charging method is 0.10 ppm or more.

[V in precipitates]/[V]≥0.30  (1)

A dual-phase stainless steel or dual-phase stainless steel seamless pipe has a certain composition, the dual-phase stainless steel or dual-phase stainless steel seamless pipe having a microstructure containing 20 to 70% austenitic phase and 30 to 80% ferritic phase by volume, the dual-phase stainless steel or dual-phase stainless steel seamless pipe having a yield strength, YS, of 448 MPa or more, and containing oxide inclusions of which oxide inclusions having an average particle diameter of 1 μm or more have a number density of 15/mm.sup.2 or less, and at most 50 mass % of the oxide inclusions having an average particle diameter of 1 μm or more are oxide inclusions containing aluminum.

Provided is a novel sintered oil-impregnated bearing superior in wear resistance and cost performance under a severe use condition where the bearing collides with a shaft due to a high load and vibration, such as a condition associated with an output shaft of an electric motor installed in a vehicle and a wiper motor installed therein. The sintered oil-impregnated bearing contains: 15 to 30% by mass of Cu; 1 to 4% by mass of C; and a remainder consisting of Fe and inevitable impurities, in which a metal structure with copper being melted therein is provided at least on a bearing surface; pearlite or a pearlite with ferrite being partially scattered therein is provided in a matrix; a copper-rich phase arranged in a mesh-like manner is also provided in the matrix; and a free graphite is dispersed and distributed in the matrix as well.