Polycrystalline solids mechanical properties

The electrical double-layer (edl) properties pose a fundamental problem for electrochemistry because the rate and mechanism of electrochemical reactions depend on the structure of the metal-electrolyte interface. The theoretical analysis of edl structures of the solid metal electrodes is more complicated in comparison with that of liquid metal and alloys. One of the reasons is the difference in the properties of the individual faces of the metal and the influence of various defects of the surface [1]. Electrical doublelayer properties of solid polycrystalline cadmium (pc-Cd) electrodes have been studied for several decades. The dependence of these properties on temperature and electrode roughness, and the adsorption of ions and organic molecules on Cd, which were studied in aqueous and organic solvents and described in many works, were reviewed by Trasatti and Lust [2]. 

The mechanical properties of materials are of enormous influence on the way these can be processed. After a molten metal has cooled to a solid, the solid metal is mechanically moulded into the desired form. The way of cooling and the final shape to a large extent determine the properties of the product. By means of a heat treatment it is possible to alter the properties of some metals. In this process the polycrystalline material is converted to a less polycrystalline form and eventually a state is reached which comes close the the ideal state, i.e. the metal is nearlv monocrvstalline (figure 10.10). 

Solute and impurity segregation to grain boundaries in polycrystalline solids is known to affect mechanical properties and engineering performances of these materials. 

---