An electropolishing or electroplating system and method for metal conveyor belts is described. In some embodiments, the system has a metal conveyor belt held in constant tension; a tank for holding an electrolytic fluid, the tank having an interior space suitable to contain the fluid, a metal plate and the metal conveyor belt; and an electrical current supply. In an electropolishing application, the current passes from the metal conveyor belt, through the fluid and into the metal plate. In an electroplating application, the current passes from the metal plate, through the fluid and into the metal conveyor belt.

An electropolishing or electroplating system and method for metal conveyor belts is described. In some embodiments, the system has a metal conveyor belt held in constant tension; a tank for holding an electrolytic fluid, the tank having an interior space suitable to contain the fluid, a metal plate and the metal conveyor belt; and an electrical current supply. In an electropolishing application, the current passes from the metal conveyor belt, through the fluid and into the metal plate. In an electroplating application, the current passes from the metal plate, through the fluid and into the metal conveyor belt.

A method of manufacturing a grain oriented electrical steel sheet includes subjecting a steel slab to a rolling process including cold rolling to obtain a steel sheet with a final sheet thickness, the steel slab containing by mass % C: 0.01% to 0.20%, Si: 2.0% to 5.0%, Mn: 0.03% to 0.20%, sol. Al: 0.010% to 0.05%, N: 0.0010% to 0.020%, at least one element selected from S and Se in a total of 0.005% to 0.040%, and the balance including Fe and incidental impurities; forming, by a chemical process, a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet; subjecting the steel sheet to decarburization annealing; applying an annealing separator thereon mainly composed of MgO; and subjecting the steel sheet to final annealing to manufacture a grain oriented electrical steel sheet.

A method of manufacturing a grain oriented electrical steel sheet includes subjecting a steel slab to a rolling process including cold rolling to obtain a steel sheet with a final sheet thickness, the steel slab containing by mass % C: 0.01% to 0.20%, Si: 2.0% to 5.0%, Mn: 0.03% to 0.20%, sol. Al: 0.010% to 0.05%, N: 0.0010% to 0.020%, at least one element selected from S and Se in a total of 0.005% to 0.040%, and the balance including Fe and incidental impurities; forming, by a chemical process, a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet; subjecting the steel sheet to decarburization annealing; applying an annealing separator thereon mainly composed of MgO; and subjecting the steel sheet to final annealing to manufacture a grain oriented electrical steel sheet.

Provided are stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, and a method of manufacturing the same. In the stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, according to an embodiment of the present invention, a ratio of Cr hydroxide/Cr oxide included in a passivation film of the stainless steel ranges from 0.5 to 1.7, and the passivation film has a contact angle (θ) of 70° or less. Thus, not only corrosion resistance may be enhanced by removing a non-conductive film formed on a surface of the stainless steel and forming a new conductive film thereon, but hydrophilicity may also be secured without additional surface treatment such as a separate coating or the like, and thus manufacturing costs may be reduced and productivity may be increased.

Provided are stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, and a method of manufacturing the same. In the stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, according to an embodiment of the present invention, a ratio of Cr hydroxide/Cr oxide included in a passivation film of the stainless steel ranges from 0.5 to 1.7, and the passivation film has a contact angle (θ) of 70° or less. Thus, not only corrosion resistance may be enhanced by removing a non-conductive film formed on a surface of the stainless steel and forming a new conductive film thereon, but hydrophilicity may also be secured without additional surface treatment such as a separate coating or the like, and thus manufacturing costs may be reduced and productivity may be increased.

An electrochemical deposition system—for the electrochemical deposition of a metal-based material (e.g., aluminum or an aluminum alloy)—comprises an electrolyte solution, at least one working electrode, and at least one counter electrode. The electrolyte solution comprises at least one imidazolium-based tetrahalo-metallate compound (e.g., alkyl methylimidazolium tetrachloroaluminate(s)) and at least one metal-containing compound (e.g., AlCl.sub.3, AlBr.sub.3) of a metal of the metal-based material to be electrodeposited on the at least one working electrode. The working electrode is configured to be exposed to the electrolyte solution. The at least one counter electrode is in contact with the electrolyte solution. In some embodiments, the system is configured for additive manufacturing of the metal-based material being electrochemically deposited. Related methods are also disclosed.

A hot-dip Sn—Zn-based alloy-plated steel sheet according to an aspect of the present invention includes: a steel sheet having a predetermined chemical composition; a diffusion alloy layer provided on one surface or both surfaces of the steel sheet; and a Sn—Zn-plated layer provided on the diffusion alloy layer, in which the diffusion alloy layer contains Fe, Sn, Zn, Cr, and Ni, an area ratio of a Sn—Fe—Cr—Zn phase to a Sn—Fe—Ni—Zn phase in the diffusion alloy layer is 0.01 or more and less than 2.5, the diffusion alloy layer has a coverage of 98% or more with respect to the one surface, the Sn—Zn-plated layer contains 1% to 20% of Zn by mass % and a remainder consisting of Sn and impurities, and an adhesion amount of the Sn—Zn-plated layer is 10 to 80 g/m.sup.2 per one surface.

A hot-dip Sn—Zn-based alloy-plated steel sheet according to an aspect of the present invention includes: a steel sheet having a predetermined chemical composition; a diffusion alloy layer provided on one surface or both surfaces of the steel sheet; and a Sn—Zn-plated layer provided on the diffusion alloy layer, in which the diffusion alloy layer contains Fe, Sn, Zn, Cr, and Ni, an area ratio of a Sn—Fe—Cr—Zn phase to a Sn—Fe—Ni—Zn phase in the diffusion alloy layer is 0.01 or more and less than 2.5, the diffusion alloy layer has a coverage of 98% or more with respect to the one surface, the Sn—Zn-plated layer contains 1% to 20% of Zn by mass % and a remainder consisting of Sn and impurities, and an adhesion amount of the Sn—Zn-plated layer is 10 to 80 g/m.sup.2 per one surface.

A pretreatment method for pretreating components, which are each formed of at least two different materials, prior to a coating process. The pretreatment method includes the steps: alkaline degreasing; chemical pickling in a first pickling medium; anodic pickling in a second pickling medium; and cathodic degreasing.