PARTICLE CHARACTERIZATION BY ELECTROKINETIC METHODS

摘要

Electrophoretic deposition (EPD) processes are mainly influenced by the surface properties of the used powder system. The electrophoretic forming process depends on the dispersibility of the powder, the stability of the resulted suspension, the electrophoretic mobility of the individual particle, and the particle interaction forces. On the other hand interaction forces are also interesting for building composite materials with the help of EPD. So it is necessary to characterize the surface properties of the particles, their behaviour in an electric field, and the influence of additive substances on these properties. Electrokinetic methods are most suitable for this investigation. Studies on the effects of pH, surface active agents, etc. on the electrokinetic potential give valuable information as to the nature on solid surfaces. In this paper possibilities and limits of electrokinetic methods but also charge formation processes and influencing variables of the electrophoretic mobility, the dispersion stability, and the particle interaction forces will be discussed.