A grain-oriented electrical steel sheet, on which magnetic domain refining treatment by strain application has been performed, has an insulating coating with excellent insulation properties and corrosion resistance. In a grain-oriented electrical steel sheet, linear strain having been applied thereto by irradiation with a high-energy beam, the linear strain extending in a direction that intersects a rolling direction of the steel sheet, an area ratio of irradiation marks within an irradiation region of the high-energy beam is 2% or more and 20% or less, an area ratio of protrusions with a diameter of 1.5 m or more within a surrounding portion of the irradiation mark is 60% or less, and an area ratio of exposed portions of steel substrate in the irradiation mark is 90% or less.

A slide ring includes a main body composed of grey cast iron, wherein at least a partial region of a functional surface has a ledeburitic microstructure at the surface. A method for producing such a slide ring includes heating a functional surface of the slide ring by irradiating with high-energy radiation, wherein the irradiation is carried out so that at least a partial region of the irradiated surface is remelted, wherein the parameters of the irradiation are selected so that at least a partial region of the functional surface has a ledeburitic microstructure after cooling.

A slide ring includes a main body composed of grey cast iron, wherein at least a partial region of a functional surface has a ledeburitic microstructure at the surface. A method for producing such a slide ring includes heating a functional surface of the slide ring by irradiating with high-energy radiation, wherein the irradiation is carried out so that at least a partial region of the irradiated surface is remelted, wherein the parameters of the irradiation are selected so that at least a partial region of the functional surface has a ledeburitic microstructure after cooling.

The invention relates to a welding device (1), in particular a laser welding device, for welding metal workpieces (3) by means of at least one welding head (2), in particular a laser welding head, which defines a working area (4). The welding device is characterized by at least one heating device (5) which acts on the working area (4) to heat up the workpiece (3), in particular before and/or after the welding process.

The present invention relates to a method and system for treatment of a surface of a metallic material component, the method comprising the steps: electro-spark treating the surface of the metallic component by means of an electro-spark electrode, wherein the metallic material is a basically ferritic, perlitic and/or austenitic steel and the method creates a thin layer with martensitic microstructures at the surface of the metallic material component. Serpentines and quartz can be incorporated by an additional step as well as the surface randomly structured by this.

The present invention relates to a method and system for treatment of a surface of a metallic material component, the method comprising the steps: electro-spark treating the surface of the metallic component by means of an electro-spark electrode, wherein the metallic material is a basically ferritic, perlitic and/or austenitic steel and the method creates a thin layer with martensitic microstructures at the surface of the metallic material component. Serpentines and quartz can be incorporated by an additional step as well as the surface randomly structured by this.

A grain-oriented electrical steel sheet, on which magnetic domain refining treatment by strain application has been performed, has an insulating coating with excellent insulation properties and corrosion resistance. The grain-oriented electrical steel sheet is obtained by irradiating a steel sheet with a high-energy beam to apply, to the steel sheet, linear strain extending in a direction that intersects a rolling direction of the steel sheet, and then re-forming an insulating coating on the steel sheet, in which in an irradiation mark region due to the high-energy beam, a ratio of an area containing defects on the insulating coating is 40% or less, a maximum width of the irradiation mark region in the rolling direction is 250 m or less, and a thickness of the insulating coating is 0.3 m or more and 2.0 m or less.

A grain-oriented electrical steel sheet, on which magnetic domain refining treatment by strain application has been performed, has an insulating coating with excellent insulation properties and corrosion resistance. The grain-oriented electrical steel sheet is obtained by irradiating a steel sheet with a high-energy beam to apply, to the steel sheet, linear strain extending in a direction that intersects a rolling direction of the steel sheet, and then re-forming an insulating coating on the steel sheet, in which in an irradiation mark region due to the high-energy beam, a ratio of an area containing defects on the insulating coating is 40% or less, a maximum width of the irradiation mark region in the rolling direction is 250 m or less, and a thickness of the insulating coating is 0.3 m or more and 2.0 m or less.

A steel sheet inspection device includes: a magnetooptic element that is able to detect, as an optical property, a magnetic domain structure of a steel sheet to be inspected; a light source that irradiates the magnetooptic element with linearly polarized light; a detector that detects the linearly polarized light with a polarization plane rotated according to the magnetic domain structure of the steel sheet transferred to the magnetooptic element; and a drive mechanism that drives at least the magnetooptic element so as to contact and separate the steel sheet and the magnetooptic element with and from each other.

A steel sheet inspection device includes: a magnetooptic element that is able to detect, as an optical property, a magnetic domain structure of a steel sheet to be inspected; a light source that irradiates the magnetooptic element with linearly polarized light; a detector that detects the linearly polarized light with a polarization plane rotated according to the magnetic domain structure of the steel sheet transferred to the magnetooptic element; and a drive mechanism that drives at least the magnetooptic element so as to contact and separate the steel sheet and the magnetooptic element with and from each other.