Electroplating rates

Sect. 5.5.2) and can be plated mechanically (i.e. hot dipping, metal spraying, etc.) and electrochemicaUy. Mechanical plating is the preferred method for layers with thickness >25 pm [21] and in which hydrogen embrittlement represents a problem [22]. With modem processes, electroplating rates up to 700 m min can be achieved [23]. During the last few years, zinc alloys (see Sect. 5.5.4.G) with cobalt (0.8%), nickel (10-14%), iron, and tin have found increased interest due to their improved corrosion stability (e.g. automotive appKcations). 

Hepel et al. [534] comparatively studied electroplating of Cu and Ni on doped and undoped P(Py)/Au and Au-only substrates. They interestingly found that electroplating rates were significantly enhanced at the CP substrates as compared to the Au-only substrates. They also found, expectedly, that the rates were higher on the... 

Electrodeposition of Metals. Citric acid and its salts are used as sequestrants to control deposition rates in both electroplating and electroless plating of metals (153—171). The addition of citric acid to an electroless nickel plating bath results in a smooth, hard, nonporous metal finish. 

Rating the results of corrosion tests on electroplated coatings cathodic to the substrate Guidance on stationary outdoor exposure corrosion tests... 

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... 

Steel objects are often protected from corrosion by electroplating with chromium. The most straightforward process would be to electrolyze a solution of Cr cations. This fails because aqueous Cr ions are not reduced at a useful rate. Instead, solutions containing chromate anions are used ... 

Figure 1. Cyclic voltammograms in MeCN(0.1M tetra-ethylammonium perchlorate) for the oxidation of (a) a copper electrode, (b) 3 mM "OH at a glassy carbon electrode, (c) 0.5 mM "OH at a copper electrode, and (d) 3 mM "OH at a copper electrode. Scan rate, 0. IV s"1 electrode area, 0.08 cm2 copper electrode prepared by electroplating Cu(C104) onto a glassy carbon electrode (GCE). ...

Table III. Rate and Faradaic Efficiency of CH4 Formation from CH3OH at Electroplated Ru Electrodes a...

A great number of measurements have been reported for articles electroplated with zinc. The various aims have been evaluation of the corrosion rate of zinc that had been plated in a number of commercial cyanide-free zinc baths," comparison of the corrosion rate of a composite material (zinc with codeposits of various oxides) and of pure zinc deposits," corrosion testing of various alloyed zinc platings (Zn-Ni, Zn-Co, Zn-Fe), with or without subsequent post-treatment. Most of the work in the last category was only recorded in internal reports. The published work consists of an examination of the corrosion behavior of a ctoomated Zn-Fe... 

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