Influence of the suspension composition on the electric field and deposition rate during electrophoretic deposition

Current and suspension conductivity measurements during electrophoretic deposition (EPD) of Al2O3 powder from different organic suspensions revealed that the suspension composition determines whether a potential drop is generated at the deposition electrode or not. An electrical resistive layer was formed during electrophoretic deposition of Al2O3 from ethanol with HNO3, HCl, poly(ethylene)imine or CH3COOH addition, whereas no potential drop was observed when depositing from a methylethylketone (MEK) + butylamine suspension. Additionally, a clear relationship was found between the yield of deposition and the magnitude of the potential drop at the deposition.