An object of the present invention is to provide magnesium oxide for an annealing separator which is useful for obtaining grain-oriented electromagnetic steel sheets with excellent magnetic properties and insulating properties. To resolve the above object, an aspect of the present invention resides in magnesium oxide for an annealing separator which has an adhesion water content and a hydration water content each falling in the quadrilateral region defined by the following points a to d as the vertices in a graph representing the adhesion water content-hydration water content relationship: a: adhesion water content: 0.25 mass %, hydration water content: 0.1 mass % b: adhesion water content: 0.60 mass %, hydration water content: 0.1 mass % c: adhesion water content: 0.40 mass %, hydration water content: 6.0 mass % d: adhesion water content: 0.20 mass %, hydration water content: 6.0 mass %.

Provided are: a grain-oriented electrical steel sheet that has excellent coating adhesiveness and an excellent magnetic property after stress relief annealing; and a production method for therefor. The grain-oriented electrical steel sheet has: a steel sheet; a coating layer A which is a ceramic coating having an oxide content of less than 30 mass % and which is disposed on the steel sheet; and a coating layer B which is an insulating tensile coating containing an oxide and which is disposed on the coating layer A. When a Gaussian fitting is performed on a .sup.31P-NMR spectrum of the coating layer B within the range of 0 to −60 ppm, the proportion of a peak area of −17 to −33 ppm to the total peak area is 30% or more.

A heatable treatment container for receiving a treatment bath for treating a surface of at least one large-format component having a diameter or dimensions in the range of 0.5 m to 12 m includes a container base with a container bottom, a container wall adjoining the container base, a removable lid, and a central heating column. The central heating column extends from the container bottom towards the removable lid or from the removable lid towards the container bottom. In an example embodiment, the central heating column extends from the container bottom over at least 50% of a height of the container wall towards the removable lid. In another example embodiment, the central heating column extends from the removable lid over at least 50% of a height of the container wall towards the container bottom.

Provided is a zinc-based plated steel sheet having a post-treated coating filmed thereon including: a steel sheet; a zinc plated layer formed on the steel sheet; and a post-treated coating formed on the plated layer, wherein the atomic ratio (O/M) of oxygen (O) to metals (M) contained in the post-treated coating is greater than 2 and less than 20, and a method for post-treating a zinc-based plated steel sheet. According to this, the zinc-based plated steel sheet having the post-treated coating formed thereon has the effects excellent in lubricity, weldability, adhesiveness, film-removing property and paintability. As the method of post-treating a zinc-based plated steel sheet of the present invention employs a simple coating method irrespective of the kind of plating layer, the process is simple and economical and the process operation cost is low.

The present disclosure presents a method and a system for modifying a surface of a substrate. The method includes an act of abrasive blasting of a part of the surface of the substrate. In the abrasive blasting, an abrasive media is provided to the part of the surface. The abrasive media is carried to the part by a first carrier. The abrasive media collides with the part of the surface and causes abrasion to the part of the surface. In the method, the first carrier includes steam. The steam of the first carrier heats the part of the surface.

The present disclosure presents a method and a system for modifying a surface of a substrate. The method includes an act of abrasive blasting of a part of the surface of the substrate. In the abrasive blasting, an abrasive media is provided to the part of the surface. The abrasive media is carried to the part by a first carrier. The abrasive media collides with the part of the surface and causes abrasion to the part of the surface. In the method, the first carrier includes steam. The steam of the first carrier heats the part of the surface.

A process for surface modification of a component includes providing a first reactor for a main procedure and a second reactor for an ancillary procedure. The first reactor is charged with a main medium, a component is provided to the first reactor, and the main procedure is performed by bathing the component in the main medium to bring about a chemical change onto a surface of the component. The second reactor is charged with an ancillary medium, the component is provided to the second reactor, and the ancillary procedure is performed by bathing the component in the ancillary medium to treat the surface of the component. The chemical change is a surface modification that takes the form of bluing or phosphatizing, the surface modification forms a conversion coating, and the component has a diameter or dimensions in the range from 0.5 m to 12 m.

A coating solution for forming an insulating film for a grain-oriented electrical steel sheet which contains one or more types of hydrous silicate powders having an average particle size of 2 m or less, and one or more types of phosphoric acids and phosphates satisfying a relation of n.sub.iM.sub.i/P.sub.i0.5, and satisfies (Formula 1). 1.5(n.sub.iM.sub.i+n.sub.jM.sub.j)/P.sub.i15 . . . (Formula 1) (P represents the number of moles of phosphorus, M represents the number of moles of metal ions derived from the phosphate, n represents the valence of the metal ions derived from the phosphate, i represents the number of types of phosphates, M represents the number of moles of metal elements in the hydrous silicate, n represents the valence of the metal elements in the hydrous silicate, and j represents the number of types of hydrous silicates).

Further lower iron loss can be achieved in a grain-oriented electrical steel sheet including: a predetermined film mainly composed of forsterite on a front and back surfaces thereof; and a plurality of grooves on the front surface thereof, in which the plurality of grooves have an average depth of 6% or more of a thickness of the steel sheet and are spaced a distance of 1 mm to 15 mm from respective adjacent grooves, the steel sheet has a specific magnetic permeability r.sub.15/50 of 35000 or more when subjected to alternating current magnetization at a frequency of 50 Hz and a maximum magnetic flux density of 1.5 T, and the steel sheet includes isolated parts having a presence frequency of 0.3/m or less, the isolated parts being separated from a continuous part of the film in an interface between the steel sheet and the film in a cross section orthogonal to the rolling direction of the steel sheet.

This disclosure relates to compositions for protecting a metallic surface susceptible to corrosion, the composition comprising a first component comprising an aqueous mixture of an acid-phosphate of chemical formula A.sup.m(H.sub.2PO.sub.4).sub.m.nH.sub.2O, where A is hydrogen ion, ammonium cation, metal cation, or mixtures thereof where m=1-3, and n=0-6; the first component solution adjusted to a pH of about 2 to about 5, the first component having a particle size distribution between 0.04 to 60 micron; and a second component, configured for combination and at least partial reaction with the first component to provide a phosphate ceramic, the second component comprising an aqueous solution or suspension of an alkaline oxide or alkaline hydroxide represented by B.sup.2mO.sub.m, B(OH).sub.2m, or mixtures thereof, where B is an element of valency 2m (m=1, 1.5, or 2) the second component solution adjusted to a pH of between 9-14.