Plate Process

Plating Processes, Harshaw Chemical Co., Solon, Ohio, Mar. 1977. 

Anodes. Lead—antimony (6—10 wt %) alloys containing 0.5—1.0 wt % arsenic have been used widely as anodes in copper, nickel, and chromium electrowinning and metal plating processes. Lead—antimony anodes have high strength and develop a corrosion-resistant protective layer of lead dioxide during use. Lead—antimony anodes are resistant to passivation when the current is frequendy intermpted. 

Alloys. Alloys consist of two or mote elements of different vapor pressures and hence different evaporation rates. As a result, the vapor phase and therefore the deposit constantiy vary in compositions. This problem can be solved by multiple sources or a single rod- or wire-fed electron beam source fed with the alloy. These solutions apply equally to evaporation or ion-plating processes. 

MSA Zinc Plating Process, Technical Bulletin, Elf Atochem North America, Philadelphia, Pa. 

Fig. 4. Flow sheet of plate processing and battery manufacturing.

V. M. HalsaU and. R. Pierson, "Plate Processing—The Heart of the Lead—Acid Battery," BCI Proceedings, June 1972. 

Copper etchants do not directly influence the electroless plating process, but are used merely to remove unwanted copper, and should not affect the deposit properties. The costs of waste treatment and disposal have led to disuse of throw-away systems such as chromic—sulfuric acid, ferric chloride, and ammonium persulfate. Newer types of regenerable etchants include cupric chloride, stabilized peroxide, and proprietary ammoniacal etchant baths. 

Plate Thickness. In plating processes, plate thickness can be predicted knowing the cathode efficiency of a particular plating solution, the current density, and time of plating. 

Properties, Specifications, and Test Methods Standard test methods are required to measure the properties of electroplated materials. Documents on plating specifications for many phases of the plating process are pubHshed by such organizations as the Federal government, the military, ASTM, ISO, SAE, etc. An excellent cross-index of these is available (37). 

Corrosion Resistance. The environment to which a plated part is to be exposed should be a part of any definition of corrosion resistance. Problems arise in testing a part in its intended environment in part because of the long time period required. In many plating processes, corrosion resistance is direcdy proportional to the plate thickness, so a specification on plate thickness is a much faster method of indirectiy measuring corrosion resistance. In specifying a corrosion resistance requirement for the production of plated goods, accelerated tests are used especially if plate thicknesses caimot be related to corrosion protection. 

Ductility Tests. The ductihty of plated metals differs considerably from the corresponding thermally cast metals. Additionally, ductihty which is an important property if parts are to be deformed after plating, varies with the chemical composition of the plating solution, as well as the operating conditions of a given plating process. Ductihty can also be important when plated parts are stressed in use. Some metal deposits have coefficients of... 

MSTMF519, Std. Methodfor Mechanical Hydrogen Embrittlement Testing of Plating Processes and Mircraft Maintenance Chemicals, American Society for Testing and Materials, Philadelphia, Pa., 1977. 

Condensation of A/, vapour can occur on all cool surfaces and the plating process is therefore not selective with regard to Some fundamental aspects concerning the formation and properties of these coatings have recently been considered ". ... 

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