Electroplating electrodeposit properties

Electroplating—the process of electrodeposition onto a metallic substrate of a thin adherent layer of a metal or alloy having desirable chemical, physical and/or mechanical properties. 

It will be seen that the design of articles to be electroplated can have a considerable effect on the corrosion resistance of the electrodeposited coating. The chief effects are the result of variations in deposit thickness, but also important are features which can influence the adhesion, porosity and physical properties of the deposit. Good design will also avoid features of the plated article capable of trapping liquids or solid contaminants which might cause more rapid corrosion. 

Addition Agent a substance added to an electroplating solution to produce a desired change in the physical properties of the electrodeposit. 

Koretzky [83] in 1963 published a review of electrodeposited magnetic films, which considers an earlier generation of storage devices. Some magnetic properties of electroplated Co alloys were tabulated by Safranek [84] and by Morral [85]. 

The structures of electroplated hard alloys have been less extensively studied than those of similar electrolessly deposited materials. Sallo and co-workers [118-120] have investigated the relationship between the structure and the magnetic properties of CoP and CoNiP electrodeposits. The structures and domain patterns were different for deposits with different ranges of coercivity. The lower-f/c materials formed lamellar structures with the easy axis of magnetization in the plane of the film. The high-Hc deposits, on the other hand, had a rod-like structure, and shape anisotropy may have contributed to the high coercivity. The platelets and rods are presumed to be isolated by a thin layer of a nonmagnetic material. 

Finally, in chapter 6, another direction of applied electrochemistry is treated by Hovestad and Janssen Electroplating of Metal Matrix Composites by Codeposition of Suspended Particles. This is another area of metals materials-science where electroplating of a given metal is conducted in the presence of suspended particles, e.g. of A1203, BN, WC, SiC or TiC, which become electrodeposited as firmly bound occlusions. Such composite deposits have improved physical and electrochemical properties. Process parameters, and mechanisms and models of the codeposition processes are described in relation to bath... 

Electrodeposited Me alloys are of great practical importance because of their unconventional electric, magnetic, mechanical and protective properties. The problem of electroplating of alloys is related to the processes of codeposition of metals from multicomponent electrolyte systems. Thermodynamic and kinetic aspects of electrochemical codeposition of metals and the processes of alloy phase formation have been discussed in details by Brenner [6.134], Gorbunova and Polukarov [6.135] and Despic [6.136]. 

Tantalum Tantalum has unique properties that make it useful for many applications, from electronics to mechanical and chemical systems. Many efforts have been made to develop an electroplating process for the electrodeposition of Ta. High-temperature molten salts were found to be efficient baths for the dectrodepo-sition of refractory metals. To the best of our knowledge, imtil now no successful attempts have been made for Ta electrodeposition at room temperature or even at low temperature in ionic liquids. We present here the first results of tantalum dec-trodeposition in the air and water stable ionic liquid 1-butyl-l-methyl-pyrrolidinium bis(tri-fiuoromethylsulfonyl)amide ([BMP][Tf2N]). 

Many metals are made by electrodeposition. Several metals are prepared by electrolysis in molten salts (Section 7.6). A variety of plating processes have been developed for the metals deposited by electroplating. Quite different, usually aqueous, electrol54es are used. Each electrolyte has characteristic features and produces deposits with quite different properties. As an example, some electrolytes for the plating of copper will be described. Other important plating processes, e.g., zinc, nickel, tin, and lead, are described in detail in the literature. ... 

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