Special techniques for grain size reduction

Based on these facts, there are several possibilities to control the crystallite size the crystallite size can be decreased by increasing the current density for a constant the crystallite size can be increased for long due to Ostwald ripening the use of organic additives (grain refiners) enables the control of the crystallization process during the time because these molecules are adsorbed on the electrode surface in a reversible way and hinder the surface diffusion of the adatoms and changing the temperature influences all diffusion processes (ion diffusion in the electrolyte, surface diffusion of the nuclei) - if small crystallite sizes are desired, the deposition should be performed at lower temperatures. 

Samples Description Deposition conditions Microhardness Average  

Note /p- pulse current density, - average current density, f- pulse frequency Source Ghosh etal. (2006) 

2 XRD pattern of pulse-plated NC-A and DC-plated NC-C alloys (Ghosh et a ., 2006). 

Pulse reverse current (PRC) technique enables intentional adjustment of the nanostructure (grain size, grain size distribution, microstress) wMeh is responsible for the physical and chemical properties by introducing anodic pulses during cathodic pulsed ciment. The average current in the PRC technique is given by the equation  

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