A method for at least locally increasing the plasticity of a metal workpiece, which contains in particular an aluminum alloy, wherein the workpiece is irradiated in order to increase its temperature, and an associated production device, is provided. In order to be able to more quickly and thoroughly heat specific regions of a metal workpiece than other regions in a targeted manner, wherein it is possible to heat these regions more quickly and thoroughly with the same radiation output, while the surface of the workpiece remains largely unaffected, it is proposed that an absorbent be applied at least locally to the workpiece prior to irradiation thereof, wherein the degree of absorption of the absorbent for the radiation is greater than the degree of absorption of the workpiece for the radiation.

The present invention relates to an annealing separator for an oriented electrical steel sheet, an oriented electrical steel sheet, and a manufacturing method of an oriented electrical steel sheet.

An annealing separator for an oriented electrical steel sheet including: a first component including a Mg oxide or a Mg hydroxide; and a second component including one kind among oxides and hydroxides of a metal selected from Al, Ti, Cu, Cr, Ni, Ca, Zn, Na, K, Mo, In, Sb, Ba, Bi, and Mn, or two or more kinds thereof, and of which Equation 1 below is satisfied, an oriented electrical steel sheet manufactured by using the same, and a manufacture method of an oriented electrical steel sheet, are provided.

0.05<[A]/[B]<10.5[Equation 1]

(In Equation 1, [A] is a content of the second component with respect to a total amount (100 wt %) of the annealing separator, and [B] is a content of the first component with respect to a total amount (100 wt %) of the annealing separator).

A manufacturing process of a hot stamped coated part comprising the following successive steps, in this order: providing a hot rolled or cold rolled steel sheet comprising a steel substrate and an aluminium-silicon alloy precoating, the precoating containing more than 50% of free aluminium and having a thickness comprised between 15 and 50 micrometers, then cutting the steel sheet to obtain a precoated steel blank, then heating the blank under non protective atmosphere up to a temperature T.sub.i comprised between T.sub.e10 C. and T.sub.e, Te being the eutectic or solidus temperature of the precoating, then heating the blank from the temperature T.sub.i up to a temperature T.sub.m comprised between 840 and 950 C. under non protective atmosphere with a heating rate V comprised between 30 C./s and 90 C./s, V being the heating rate between the temperature T.sub.i and the temperature T.sub.m, in order to obtain a coated heated blank, then soaking the coated heated blank at said temperature T.sub.m for a time t.sub.m comprised between 20 s and 90 s, then hot stamping the blank in order to obtain a hot stamped coated part, then cooling said stamped part at a cooling rate in order to form a microstructure in the steel substrate comprising at least one constituent chosen among martensite or bainite.

A manufacturing process of a hot stamped coated part comprising the following successive steps, in this order: providing a hot rolled or cold rolled steel sheet comprising a steel substrate and an aluminium-silicon alloy precoating, the precoating containing more than 50% of free aluminium and having a thickness comprised between 15 and 50 micrometers, then cutting the steel sheet to obtain a precoated steel blank, then heating the blank under non protective atmosphere up to a temperature T.sub.i comprised between T.sub.e10 C. and T.sub.e, Te being the eutectic or solidus temperature of the precoating, then heating the blank from the temperature T.sub.i up to a temperature T.sub.m comprised between 840 and 950 C. under non protective atmosphere with a heating rate V comprised between 30 C./s and 90 C./s, V being the heating rate between the temperature T.sub.i and the temperature T.sub.m, in order to obtain a coated heated blank, then soaking the coated heated blank at said temperature T.sub.m for a time t.sub.m comprised between 20 s and 90 s, then hot stamping the blank in order to obtain a hot stamped coated part, then cooling said stamped part at a cooling rate in order to form a microstructure in the steel substrate comprising at least one constituent chosen among martensite or bainite.

There is provided a method of manufacturing an Ni-base superalloy which enables a uniform coat of a glass lubricant to be maintained even after heated to hot forging temperature. The method of manufacturing an Ni-base superalloy in which a forging stock containing an Ni-base superalloy, coated with a lubricant, is subjected to hot forging includes: a preliminary oxidation step of previously generating a Cr oxide coating film having a film thickness of 0.5 to 50 m on the forging stock thereby to obtain a preliminarily oxidized material; a lubricant coating step of coating the preliminarily oxidized material with a glass lubricant containing borosilicate glass as a main component thereby to obtain a material to be forged; and a hot forging step of hot forging the material to be forged thereby to obtain a hot forged material.

There is provided a method of manufacturing an Ni-base superalloy which enables a uniform coat of a glass lubricant to be maintained even after heated to hot forging temperature. The method of manufacturing an Ni-base superalloy in which a forging stock containing an Ni-base superalloy, coated with a lubricant, is subjected to hot forging includes: a preliminary oxidation step of previously generating a Cr oxide coating film having a film thickness of 0.5 to 50 m on the forging stock thereby to obtain a preliminarily oxidized material; a lubricant coating step of coating the preliminarily oxidized material with a glass lubricant containing borosilicate glass as a main component thereby to obtain a material to be forged; and a hot forging step of hot forging the material to be forged thereby to obtain a hot forged material.

A resist coating for etching use which enables high speed and high accuracy patterning is provided by applying, to a steel strip, a negative resist ink which solidifies upon exposure to light; drying the ink to form a resist coating; then irradiating the steel strip with light while moving a mask member in synchronization with a traveling speed of the steel strip, the mask member being configured to cover a surface of the resist coating to block light, to thereby solidify a portion of the resist coating not covered with the mask member to form a solidified portion; and removing an unsolidified portion other than the solidified portion with a developing solution. Subsequently, by dissolving and removing by etching a portion of the steel strip below the removed portion of the resist coating, a fine and uniform linear groove can be formed in a surface of the steel strip.

A high-strength cold-rolled steel sheet having excellent bending workability includes, by weight %, 0.13-0.25% of carbon (C), 1.0-2.0% of silicon (Si), 1.5-3.0% of manganese (Mn), 0.08-1.5% of aluminum (Al)+chromium (Cr)+molybdenum (Mo), 0.1% or less of phosphorus (P), 0.01% or less of sulfur (S), 0.01% or less of nitrogen (N), the remainder of Fe and inevitable impurities, and comprises, by area fraction, 3-25% of ferrite, 20-40% of martensite, and 5-20% of retained austenite, in which a nickel-rich layer formed of nickel (Ni) introduced from the outside is provided on a surface layer portion, and the concentration of nickel (Ni) at a depth of 1 m from the surface may be greater than or equal to 0.15 wt %.

A graphene-coated steel sheet and a method for manufacturing the same are provided. The graphene-coated steel sheet includes a steel sheet and a graphene layer formed on the steel sheet. Therefore, the graphene-coated steel sheet can be useful in preventing corrosion of iron, such as oxidation of iron, and has remarkably excellent thermal conductivity and electrical conductivity, as well as excellent heat resistance resulting from thermal stability of graphene. Also, the method can be useful in manufacturing a high-quality graphene-coated steel sheet having a monocrystalline form and showing substantially no defects or impurities.

A graphene-coated steel sheet and a method for manufacturing the same are provided. The graphene-coated steel sheet includes a steel sheet and a graphene layer formed on the steel sheet. Therefore, the graphene-coated steel sheet can be useful in preventing corrosion of iron, such as oxidation of iron, and has remarkably excellent thermal conductivity and electrical conductivity, as well as excellent heat resistance resulting from thermal stability of graphene. Also, the method can be useful in manufacturing a high-quality graphene-coated steel sheet having a monocrystalline form and showing substantially no defects or impurities.