الفهرس 
Chapter One - IntroductionOnly 14 pages are availabe for public view
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Abstract
Electrodeposited zinc coatings have long been recognized as effective barrier and sacrificial coatings for ferrous substrates. They widely used in the field of corrosion resistant coatings and energy storage devices. The electrodeposition of Zn and its alloys from ionic liquids has attracted attention in the recent years. Compared with aqueous solutions, ionic liquids have some unique properties such as usually extremely low vapor pressures, good thermal stability and electrical conductivity as well as wide electrochemical windows. In water the electrodeposition of zinc and its alloys is usually accompanied by hydrogen evolution and often low current efficiencies. Problems associated with hydrogen evolution can in principle be avoided by employing ionic liquids as they can be made water free. In this work, the effect of additives on deposit morphology and grain size in electrodeposition of zinc coatings from ionic liquid was studied. Electrodepositions of zinc coatings based on eutectic mixtures of choline chloride (ChCl) with urea in a molar ratio of 2:1 were carried out. Plain carbon steel and dual phase steel as two different substrates were used to study their effects on the deposit morphology. Effects of 0.3M additives; acetonitrile and ethylen diamine on the deposit grain size and surface morphology were investigated, Deposit morphologies and grain size were examined using a high-resolution field emission scanning electron microscopy; QUANTA FEG 250, provided with energy dispersive X-ray spectroscopy (EDX). The results revealed that the deposit morphologies and grain size were influenced by both substrates change and additives types. When the pulse current and acetonitrile as an additive were applied, a define cubic shape with average grain size of 0.499μm were obtained.