Subject electroplating

Satisfactory service of an electroplated article is not achieved, however, unless adequate care is given to the choice of deposited metal, its thickness, the technique of application, and the design of the article. The choice of metal deposit is primarily determined by the basis metal, i.e. the metal from which the article is made, and the actual conditions to which the plated article will be subjected during service. In addition, however, attractive appearance and reasonable cost are also important considerations. 

Method for measurement of impedance of anodic coatings on aluminium Recommended practice for rating of electroplated panels subjected to atmospheric exposure... 

Electrodeposited chromium coatings. Electrolytic corrosion testing Coatings cathodic to the substrate-rating of electroplated test specimens subjected to corrosion tests... 

Waste reduction methods reduce the amount of waste generated and also the amount subject to environmental regulations. Hence, these practices can help an electroplating shop comply with requirements and save money. The shop s owner or manager must be committed to waste reduction and pass that commitment on to the employees. 

Several studies of occupational exposures and one study with a human subject were located. In the occupational exposures (summarized in Table 5- 3), neurological symptoms consistent with cyanide intoxication were demonstrated, but the likelihood of concomitant exposure to other chemicals could not be ruled out. For example, cleaners and cutting oils, as well as sodium and copper cyanide, may be present in electroplating operations (ATSDR 1997). The experimental human study involved the exposure of a single subject and a dog to a high concentration for a short exposure period. 

The subject of alloy electroplating is being dealt with by an ever-increasing number of scientific publications (close to 200 in the last five years in the Journal of the Electrochemical Society alone ). The reason for this seems to be the vastness of the number of possible alloy combinations and the concomitant possible practical applications. 

Surface characterization is of vital importance in electroplating processes. First there is the preparation of the surface to receive the plating and the need to know the surface s suitability to receive and its condition after the completion of plating. Then there is the in situ characterization during plating, which is the subject of Chapter 14. 

Silver and gold were probably the first metals to be electroplated27 and were the subject of a patent which could be said to have started the electroplating industry.28 Both metals are normally plated from cyanide baths and the processes have enjoyed some prominence since World War II as electronics technology has developed and the good electrical conductivity and chemical resistance of the metals has been attractive. 

In some applications (such as military equipment) a very high standard of effectiveness is required—and it can be attained by electroplating over the electroless copper to make thicker deposits. When components will be subjected to handling it may be desirable to enhance the durability of shielding by adding electroplated nickel-chromium finishes. 

Electro-deposition of Cobalt.1—Although nickel has been very largely used for commercial electroplating purposes, there would appear to be a useful field for a cobalt electroplate industry. The earlier literature on the subject is full of contradictions,2 but this is readily understood when it is remembered what an important influence upon the nature of deposited metals is exerted by different factors such as temperature, current density, chemical composition of the solution employed, etc. 

Virgin ACFs, AW2001, supplied by Taiwan Carbon Co. was used in this work. To sensitize the surface of ACFs were immersed in a solution composed of acidified tin chloride solution at concentration of S g-f for 5 min at room temperature, and followed by a rinse with distilled water. The ACFs were successively subjected to a copper electroplating in copper plating solutions with varying treatment time. 

The heterocyclic character of caramels from ammonia and amino acid processes may suggest that such caramels may be quatemized by metal ions to form metal coordination compounds. Indeed, such complexes with Cu, Cd " ", Ni " ", and Zn have been found, and studied by Agarwal and co-workers. Because caramel may be a transporter of ions in solution, it has been the subject of a study of its surface activity and its usefulness as a brightener in electroplating baths. ... 

Thirty-two workers in an electroplating plant accidentally drank water contaminated with nickel sulfate and chloride (1.6 g Ni L ) (Sunderman et al. 1988b). Twenty of the workers promptly developed symptoms including nausea, vomiting, abdominal discomfort, diarrhea, giddiness, lassitude, headache, cough, and dyspnea that typically lasted for a few hours, but which persisted for 1 to 2 days in seven cases. In a few cases, laboratory tests showed transiently elevated levels of blood reticulocytes, urine albumin, and serum bilirubin. All subjects recovered rapidly, without evident sequelae, and returned to work by the eighth day after exposure. 

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