The present invention is directed to a particle having a chemical conversion coating on at least a portion of the particle surface. The present invention is further directed to a coated substrate comprising: (a) a surface that has been contacted with a particle having a chemical conversion coating on at least a portion of the particle surface such that at least some portion of the substrate becomes treated with the conversion coating.

Provided is a low-cost cold rolled steel sheet for zirconium-based chemical conversion treatment that contains Si and Mn and has excellent zirconium-based chemical convertibility even when a relatively large amount of Si-based oxide and Si—Mn-based oxide exists on the steel sheet surface. A cold rolled steel sheet for zirconium-based chemical conversion treatment comprises a chemical composition containing, in mass %, C: 0.05% to 0.30%, Si: 0.01% to 1.4%, Mn: 0.14% to 3.2%, P: 0.10% or less, and S: 0.01% or less, with a balance consisting of Fe and inevitable impurities, wherein a Si/Mn mass ratio in steel is 0.10 to 0.7, and a surface coating ratio of steel sheet surface layer oxides having Si content of 10 mass % or more is 40% or less.

To provide a cationic electrodeposition coating composition manifesting excellent anticorrosive property at edges and in flat areas, along with finish quality, even in a state of thin film, as well as a coated article demonstrating these excellent coating film performances, the cationic electrodeposition coating composition includes an amino group-containing epoxy resin (A), a blocked polyisocyanate compound (B), and crosslinked epoxy resin particles (C), wherein the crosslinked epoxy resin particles (C) are contained by 0.1 to 40 parts by mass relative to the total mass in solids content of the amino group-containing epoxy resin (A) and blocked polyisocyanate compound (B); the number-average molecular weight of the crosslinked epoxy resin particles (C) is under 100,000; and/or the volume-average particle size of the crosslinked epoxy resin particles (C) is 30 to 1,000 nm.

The invention has as its object the provision of a metal-fiber reinforced plastic composite able to more reliably prevent occurrence of an electrolytic corrosion action when forming a composite of a metal member and a fiber reinforced plastic layer comprising reinforcing fiber (carbon fiber) and a matrix resin.

A metal-fiber reinforced plastic composite 1 according to the present invention comprises a metal member 10, an insulating layer 30 arranged on at least part of a surface of the metal member 10 and comprising a first matrix resin 31 containing nonconductive fiber 32, and a CFRP layer 40 arranged on at least part of a surface of the insulating layer 30 and comprising a second matrix resin 41 containing carbon fiber 42, wherein, when viewing the surface of the metal member 10 from vertically above, the CFRP layer 40 is positioned at the inside of a region where the insulating layer 30 is present and an outer edge of the CFRP layer 40 and an outer edge of the insulating layer 30 are 0.2 mm or more apart. Due to this, it is possible to prevent electrolytic corrosion of the metal member.

Provided are coated metal, the metal having improved properties due to a novel coating, a coating-forming treatment solution for forming the novel coating, and a method for producing the coated metal that has the novel coating. The coated metal includes metal and a coating formed on the metal. The coating includes Si, P, and O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, and Mn. The coating includes a compound having a NASICON-type crystal structure represented by the general formula M.sup.IM.sup.IV.sub.2(M.sup.VO.sub.4).sub.3.

Provided are coated metal, the metal having improved properties due to a novel coating, a coating-forming treatment solution for forming the novel coating, and a method for producing the coated metal that has the novel coating. The coated metal includes metal and a coating formed on the metal. The coating includes Si, P, and O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, and Mn. The coating includes a compound having a NASICON-type crystal structure represented by the general formula M.sup.IM.sup.IV.sub.2(M.sup.VO.sub.4).sub.3.

What is provided is a new and improved metal-carbon fiber reinforced resin material composite in which the galvanic corrosion of dissimilar materials of a metal member is suppressed and electrodeposition coatability is excellent and a method for manufacturing the metal-carbon fiber reinforced resin material composite. A metal-carbon fiber reinforced resin material composite according to the present invention has a metal member, a resin coating layer disposed on at least a part of a surface of the metal member, and a carbon fiber reinforced resin material containing a matrix resin and a carbon fiber material present in the matrix resin, the resin coating layer contains any one or more kinds selected from the group consisting of metal particles, intermetallic compound particles, conductive oxide particles, and conductive non-oxide ceramic particles as conductive particles and further contains a binder resin, and the conductive particles have a powder resistivity at 23° C. to 27° C. of 7.0×10.sup.7 Ω.Math.cm or less and contain one or more selected from the group consisting of Zn, Si, Zr, V, Cr, Mo, Mn, and W.

An insulating coating for an electrical steel sheet is provided that is formed on a surface of a base metal of the electrical steel sheet and that contains a polyvalent metal phosphate of one or more elements selected from Al, Zn, Mg and Ca, and has an enriched layer of a divalent metal at an interface with the surface of the base metal. An enrichment of the divalent metal contained in the enriched layer is 0.01 g/m.sup.2 or more and less than 0.2 g/m.sup.2.

An insulating coating for an electrical steel sheet is provided that is formed on a surface of a base metal of the electrical steel sheet and that contains a polyvalent metal phosphate of one or more elements selected from Al, Zn, Mg and Ca, and has an enriched layer of a divalent metal at an interface with the surface of the base metal. An enrichment of the divalent metal contained in the enriched layer is 0.01 g/m.sup.2 or more and less than 0.2 g/m.sup.2.

Provided herein are corrosion resistant metal substrates and methods for producing the same by thermal modification. The disclosure provides methods for producing corrosion resistant substrates by producing a pretreatment film on a surface of a metal substrate and heating the pretreated metal substrate. In particular, the metal substrate and/or the pretreated metal substrate of these methods is in an F temper, a T4 temper, or a T6 temper.