A mathematical description of the kinetics of the electrophoretic deposition process for Al2O3-based suspensions

The yield during electrophoretic deposition is modeled incorporating the changing electric field over the suspension, due to a potential drop over the growing deposit, assessed from on-line measurements of the current flowing through the deposition cell and the conductivity of the suspension during electrophoretic deposition. The kinetic model is validated for Al2O3 suspensions with different powder loads based on methylethylketone with n-butylamine and ethanol with polyethyleneimine or HNO3, suspensions with, respectively, a constant and a decreasing electric field during deposition. The need for a powder concentration correction, even at volume fractions down to 0.03, and the incorporation of a changing electric field is experimentally proven to be essential in order to describe the deposition yield more accurately than predicted from the Hamaker equation.