Manufacturing of Advanced Ceramic Components via Electrophoretic Deposition

Abstract

By means of electrophoretic deposition (EPD) ceramic or glass components and composites can be shaped fast with low energy input (electric field strengths in the range of 0.5 to 20 V/cm). High green densities up to 83% of the theoretical value could be achieved using suspensions with comparably low solid matter content (less than 75 wt.%) with optimised particle size distribution. The low viscosity of these suspension ({approx} 4 to 500 mPa.s) enables to deagglomerate effectively the suspended powders. Furthermore, the deposition rate is independent of the particle size. This enables the fast manufacture of ceramic of advanced glass and ceramic components from nanosized powders. Via electrophoretic deposition of nanosized particles within the pores of a green body a homogeneous densification can be achieved. Furthermore, components with functionally graded density, pore size or/and graded chemical composition were manufactured by means of electrophoretic impregnation (EPI). Another possible application of the EPI is the incorporation of secondary phases, that are difficult to incorporated from the fluid phase, into ceramic and glass-matrices. (orig.)