A method of annealing of steel sheets is provided which includes a first step consisting in fully oxidizing the surface of such steel sheet thus creating a fully oxided surface layer, a second step consisting in selectively oxidizing elements other than iron of such steel, in an area extending under said fully oxided layer, thus creating a selectively oxided internal layer and a third step consisting in fully reducing said fully oxided surface layer.

Provided is a grain-oriented electrical steel sheet that can benefit from the iron loss improving effect by groove formation while effectively suppressing a decrease in magnetic flux density. A grain-oriented electrical steel sheet comprises predetermined linear grooves, wherein in each linear groove, a proportion of predetermined flat portions to an entire length of the linear groove is 30% or more and 90% or less, the number of flat portions each of which is continuous for a predetermined length is 10 or more per 100 cm.sup.2 surface area, and a ratio of ten-point average roughness Rzjis to average depth D is 0.1 or more and 1 or less.

Provided is an annealing separating agent composition for a grain-oriented electrical steel sheet, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet. The annealing separating agent composition for a grain-oriented electrical steel sheet according to an embodiment of the present invention contains 30 to 70% by weight of a calcium compound, and the remainder of magnesium oxide or magnesium hydroxide on a solid basis.

Provided is an annealing separating agent composition for a grain-oriented electrical steel sheet, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet. The annealing separating agent composition for a grain-oriented electrical steel sheet according to an embodiment of the present invention contains 30 to 70% by weight of a calcium compound, and the remainder of magnesium oxide or magnesium hydroxide on a solid basis.

The present invention relates to a self-collapsed protective coating composition and use thereof. In particular, the invention relates to a self-collapsed protective coating composition for hot stamping of steel material, which can protect the surface of steel material from oxide scale and provide ease for subsequent welding.

The present invention provides an annealing separator composition, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet.

An annealing separator composition for a grain-oriented electrical steel sheet according to an embodiment of present invention comprising: on the basis of total solid 100 wt %, 5 to 70 wt % of mullite; and the remainder being magnesium oxide or magnesium hydroxide.

The present invention provides an annealing separator composition, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet.

An annealing separator composition for a grain-oriented electrical steel sheet according to an embodiment of present invention comprising: on the basis of total solid 100 wt %, 5 to 70 wt % of mullite; and the remainder being magnesium oxide or magnesium hydroxide.

Provided is an annealing separating agent composition for a grain-oriented electrical steel sheet, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet. The annealing separating agent composition for a grain-oriented electrical steel sheet according to an embodiment of the present invention contains 30 to 70% by weight of a calcium compound, and the remainder of magnesium oxide or magnesium hydroxide on a solid basis.

A method for producing a component made of a steel product coated with an AlSi protective coating, includes: providing a substrate consisting of a steel produced coated with an AlSi protective coating, heating the substrate to a temperature T1 such that the AlSi protective coating is only partially pre-alloyed with Fe of the steel product, cooling the pre-alloyed substrate to room temperature, applying a corrosion protection oil to the surface of the pre-alloyed substrate, wherein the oil consists of a composition containing fatty acid ester, transporting the pre-alloyed substrate to which the oil has been applied, heating the pre-alloyed substrate to which the oil has been applied to a temperature T2 such that the AlSi protective coating is fully alloyed with Fe of the steel product and the oil is removed without leaving residue, and shaping the re-heated substrate to form the component.

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.