Processing methods electrophoretic deposition

Over the past few years, a large number of experimental approaches have been successfully used as routes to synthesize nanorods or nanowires based on titania, such as combining sol-gel processing with electrophoretic deposition,152 spin-on process,153 sol-gel template method,154-157 metalorganic chemical vapor deposition,158-159 anodic oxidative hydrolysis,160 sonochemical synthesis,161 inverse microemulsion method,162 molten salt-assisted and pyrolysis routes163 and hydrothermal synthesis.163-171 We will discuss more in detail the latter preparation, because the advantage of this technique is that nanorods can be obtained in relatively large amounts. 

Another possibility of ceramic material application is the use of coatings and foams inside, for example, metallic microstructure devices. Here, well-known technologies such as CVD processes, sputtering, electrophoretic deposition, sol-gel methods in combination with spin coating, dip coating, or wash coating methods, or the use of anodic oxidation for aluminum-based devices will lead to either dense, protective ceramic coatings or porous layers used as catalyst support. 

The electrocoat process for primer coating involves the electrophoretic deposition of charged colloidal resinous particles in aqueous dispersion onto a conductive substrate such as an automobile body. The process is universally favored because once the paint particles are deposited, they insulate the body from further deposition at that point. The impressed electric field thereby causes the migration of paint particles to uncoated areas. The result is an extremely uniform, coherent and defect free coating-even on sharp edges and in recessed areas inaccessible to other methods. 

One-step electropolymerization deposition processes are envisaged as the most interesting deposition methods in view of potential technological applications. For this reason, there is a growing interest in the integration of materials obtained in such way to obtain multifunctional nanostructured composites and hybrid materials. The selective localization through electrophoretic deposition of nanotubes at the interface of polymers to obtain flexible, transparent and conductive materials could represent a novel approach. 

This chapter reviews the novel fabrication process of continuous SiC SiC composites based on electrophoretic deposition (EPD). EPD process is very effective for achieving relatively homogeneous carbon coating with the thickness of several tens to hundreds nanometers on SiC fibers. Carbon interface with the thickness of at least 100 nm formed by EPD acts effectively for inducing interfacial debonding and fiber pullout during fracture, and the SiCj/SiC composites show excellent mechanical properties. From these results, it is demonstrated that the fabrication process based on EPD method is expected to be an effective way to control the interfaces of SiC SiC composites and to obtain high-performance SiC SiC composites. 

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