These steel sheet for hot stamping and hot-stamping formed body have predetermined chemical composition and metallographic structures, and, in textures of a surface layer region and an inside region, ratios between a pole density of an orientation group consisting of {001}<1-10> to {001}<−1-10> and a pole density of an orientation group consisting of {111}<1-10> to {111}<−1-12> are controlled.

A high-ductility, high-strength steel sheet having excellent close-contact bendability and a method for producing the same. The steel sheet has a specified chemical composition and a microstructure comprising, by area percentage, 50% or more of a ferrite phase, 5% to 30% of a pearlite phase, and 15% or less in total of bainite, martensite, and retained austenite, in which the area percentage of ferrite grains each containing three or more cementite grains having an aspect ratio of 1.5 or less is 30% or less, and the number of inclusions having a particle size of 10 μm or more present in a portion extending from a surface to a ¼ thickness position is 2.0 particles/mm.sup.2 or less.

A rolled steel sheet, for press hardening is provided, having a chemical composition where Ti/N>3.42, and the carbon, manganese, chromium and silicon contents satisfy: $2.6C+\frac{\mathrm{Mn}}{5.3}+\frac{\mathrm{Cr}}{13}+\frac{\mathrm{Si}}{15}\ge 1.1\%.$
The sheet has a nickel content Ni.sub.surf at any point of the steel in the vicinity of the surface over a depth Δ, such that: Ni.sub.surf >Ni.sub.nom, Ni.sub.nom denoting the nominal nickel content of the steel, and such that, Ni.sub.max denoting the maximum nickel content within Δ: $\frac{\left({\mathrm{Ni}}_{\max }+{\mathrm{Ni}}_{\mathrm{nom}}\right)}{2}\times \left(\Delta \right)\ge 0.6,$
and such that: $\frac{\left({\mathrm{Ni}}_{\max }-{\mathrm{Ni}}_{\mathrm{nom}}\right)}{\Delta }\ge 0.01$
and the surface density of all of the particles D.sub.i and the surface density of the particles D.sub.(>2 μm) larger than 2 micrometers satisfy, at least to a depth of 100 micrometers in the vicinity of the surface of said sheet:
D.sub.i+6.75 D.sub.(>2 μm) <270
D.sub.i and D.sub.(>2 μm) being expressed as number of particles per square millimeter, and said particles denoting all the oxides, sulfides, and nitrides, either pure or combined such as oxysulfides and carbonitrides, present in the steel matrix.

A railway wheel in which formation of a quenched layer can be suppressed in the production process is provided. The railway wheel according to the present embodiment has a chemical composition consisting of, in mass %, C: 0.80 to 1.15%, Si: 1.00% or less, Mn: 0.10 to 1.20%, P: 0.050% or less, S: 0.030% or less, Al: 0.005 to 0.190%, N: 0.0200% or less, Nb: 0.005 to 0.050%, Cr: 0 to 0.25%, and V: 0 to 0.12%, with the balance being Fe and impurities. In the microstructure of a rim part of the railway wheel, an area fraction of pro-eutectoid cementite is 0.1 to 1.5% and an area fraction of pearlite is 95.0% or more.

A steel consists of, in mass %, C: 0.25 to 0.45%, Si: 0.10 to 0.50%, Mn: 0.40 to 0.70%, P: 0.015% or less, S: 0.005% or less, Cr: 0.80 to 1.50%, Mo: 0.17 to 0.30%, V: 0.24 to 0.40%, Al: 0.005 to 0.100%, N: 0.0300% or less, O: 0.0015% or less, and the balance being Fe and impurities, and satisfies Formula (1) to Formula (4) described in the present specification, wherein: its microstructure is composed of ferrite and pearlite having a total area fraction of 5.0 to 100.0%, and a hard phase having a total area fraction of 0 to 95.0%; a proportion of a total area of CaO—CaS—MgO—Al.sub.2O.sub.3 composite oxides with respect to a total area of oxides in the steel is 30.0% or more; and a number density of oxides having an equivalent circle diameter of 20.0 μm or more is 15.0 pieces/mm.sup.2 or less.

The present disclosure provides a method for controlling an amount of silicon added to ductile cast iron, a method for casting ductile cast iron, and a cast product, which relate to the technical fields of metallurgical and cast iron alloys. The method for controlling an amount of silicon added to ductile cast iron includes smelting ductile cast iron using scrap steel as a raw material. After the scrap steel is melted into molten iron, a copper alloy is added so that the molten iron has a copper equivalent of 0.8% to 1.0%, wherein the copper equivalent is controlled by formula (II). Then, ferrosilicon is added so that the content of silicon added to the molten iron satisfies formula (I).

A galvannealed steel sheet having a steel substrate coated with a first alloy layer with iron and nickel directly topped by a second alloy layer based on zinc, the first and second alloyed layers being alloyed through diffusion such that the second alloy layer includes from 5 to 15 wt.% of iron, from 0 to 15 wt.% of nickel, a balance being zinc.

A steel sheet for hot stamping includes an amount of 0.17 wt % to 0.25 wt % of carbon (C), an amount of 0.3 wt % to 1.0 wt % of silicon, an amount of 0.6 wt % to 1.0 wt % of manganese (Mn), an amount of 0.02 wt % or less of phosphorus (P), an amount of 0.01 wt % or less of sulfur (S), an amount of 0.1 wt % to 1.0 wt % of aluminum (Al), an amount of 0.001 wt % to 0.005 wt % of boron (B), an amount of 0.01 wt % to 0.1 wt % of titanium (Ti), an amount of 0.02 wt % to 0.06 wt % of niobium (Nb), an amount of 0.3 wt % to 1.0 wt % of a sum of at least one of chromium (Cr), nickel (Ni), and molybdenum (Mo), and the balance of iron (Fe) and other unavoidable impurities; and also a microstructure including ferrite and pearlite.

An embodiment of the present invention provides a steel sheet for hot press, including carbon (C) in an amount of 0.03 to 0.15 wt%, silicon (Si) in an amount of 0.1 to 1.5 wt%, manganese (Mn) in an amount of 1.0 to 2.0 wt%, phosphorus (P) in an amount of 0.1 wt% or less, sulfur (S) in an amount of 0.01 wt% or less, boron (B) in an amount of 0.0005 to 0.005 wt%, a sum of one or more of titanium (Ti), niobium (Nb), and vanadium (V) in an amount of 0.01 to 1.0 wt%, chromium (Cr) in an amount of 0.01 to 0.5 wt%, the balance of iron (Fe), and other unavoidable impurities. The steel sheet for hot press includes MnS-based inclusions, and an area fraction of the MnS-based inclusions is 5 % or less.

An improved grinding ball may include a carbon content of 1.1 to 1.4 wt %, a chromium content of 10 to 14 wt %, a manganese content of 0.8 to 1.5 wt %, a silicon content of 0.6 to 1 wt %, a molybdenum content of less than 1 wt %, a nickel content of less than 1 wt %, any impurities with a total content of less than 0.5 wt %, the balance to obtain 100% being iron. The grinding ball includes a discrete distribution of chromium carbides as opposed to a network distribution.