Decorative electrodeposited coatings

Standard Method of Corrosion Testing of Decorative Electrodeposited Coatings by the Coirodkote Procedure... 

ASTM Standard B 380 Standard Method of Corrosion Testing of Decorative Electrodeposited Coatings by tbe Corrodkote Procedure, Annual Book of ASTM Standards, Vol. 03.02, ASTM International, West Conshohocken, PA, 2001. 

B 380 Method o1 corrosion testing of decorative electrodeposited coatings by the Corrodkote... 

Watts bath — The Watts bath is the classical electrolyte for the -> electrodeposition of functional nickel coatings. It contains nickel sulfate (240-450 gL-1 of the hexahy-drate), nickel chloride (45-90 gL-1 of the hexahydrate), and boric acid (30-50 g L-1) and is usually operated between pH 2 and 4.5 and at 40-70 °C. The chloride content of the bath is crucial to ensure the dissolution of the nickel anode. In combination with - leveling agents and brighteners the Watts bath is also used for decorative nickel coatings. Its applicability for -> electroforming is limited due to tensile stresses in the deposits. 

Protective coatings are used extensively on metal or semiconductor surfaces to isolate them or limit access of an aggressive environment (17,18). Frequently these coatings are multilayered and complex in structure, as for example in automobile paints. In this case, the innermost coating is either hot-dipped or electrodeposited zinc ("galvanizing"), over which a zinc-rich polymer-chromate undercoat is placed. The decorative top coat provides a physical barrier to the transport of water and ionic species. It is important to note, however, that protection is achieved electrochemically by the galvanic action of zinc on steel and by the inhibiting action of chromate toward oxidation. 

DiBaii, G. A., Hawk, G., and Baker, E. A., Corrosion Performance of Decorative Electrodeposited Nickel and Nickel Iron Alloy Coating, Atmospheric Corrosion of Metals, ASTM STP 767,... 

Wearmouth has described the production of nickel-cobalt, nickel-manganese, and nickel-chromium alloy coatings for non-decorative uses. The nickel-cobalt and nickel-manganese are electrodeposited direct from sulphamate-based solutions, the nickel-cobalt alloys offering higher hardness than the nickel-manganese alloys, which are restricted to a relatively... 

PROTECTIVE COATING. A film or thin layer of metal glass of paint applied to a substrate primarily to inhibit corrosion, and secondarily for decorative purposes, Metals such as nickel, chromium, copper, and tin are electrodeposited on the base metal paints may be sprayed or brushed on. Vitreous enamel coatings are also used these require baking. Zinc coating are applied by continuous bath process in which a strip of ferrous metal is passed through molten zinc. 

The objective of this chapter is to illustrate the use of microradiology with coherent x-rays [ 1 ] to investigate open problems in electrodeposition. Metal electrodeposition is an old and widely exploited technique, one of the most frequently used for protective and decorative coating [2], semiconductor device fabrication processes, and other industrial tasks [3,4],... 

A panchromatic sensitization as well as a considerable efficiency in photon to electron conversion can be obtained by functionalizing titania nanostructures (nanotubes as well as nanoparticles) with CdSe. In this case both chemical and electrochemical deposition leads to morphologically similar surfaces where CdSe can be observed to decorate each nanotube. As previously observed, the electrodeposition is the preferred method for obtaining a more homogeneous coating of each nanostructure, where CdSe covers almost completely the entire length of every nanotube, also occluding their mouths (Fig. 39). 

Thin coatings of chromium [139] are applied over another electrodeposited layer, usually nickel or copper, as a decorative, nonstaining finish these thin (250 pm) layers are porous. Hard chromium plating is used where advantage may derive from the high hardness and wear resistance, or the low coefficient of friction, of such deposits. Chromium electrodeposits are not suitable for use at high... 

Recently anchoring nanosized SnO on anisotropic nanostructures of conducting polymers has attracted much attention, emerging the ID or 2D nanocomposites as high-performed anode materials. Zhang et al. employed a facile two-step electrochemical reaction method including electropolymerization and electrodeposition to fabricate SnO -nanoparticles-decorated PPy nanowires [108]. SEM and TEM reveal that the surface of PPy nanowires was densely coated with SnO nanoparticles (Figure 7.15). 

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