Deposition Patterns of Porcelain Coatings Obtained by Electrophoretic Deposition in Acetone. Part 1. Voltage and Time Effect

Abstract

Homogeneous surface morphologies are of interest to form different functional coatings. In order to verify if these morphologies could be observed and controlled in an electrophoretic cell, voltage and time effect have been studied on the deposition patterns of porcelain particle on a stainless steel substrate. The suspensions were prepared at 1 wt % of porcelain submicronic particles using acetone as dispersing media. The EPD experiments were carried out at 400, 600, and 800 V at deposition times of 1, 15, 30, 45, and 60 s. The morphology of the particle deposit patterns were characterized by scanning electron microscopy. At 1 s, submicronic particles without any pattern formation were observed on the stainless steel substrate. At subsequent deposition times, the patterns evolved from worm like forms to ring like forms and finally to labyrinth-type agglomerates of particles depending on voltage and deposition times. At deposition times longer than 60 s, the particle deposit patterns were difficult to observe. The coatings obtained at deposition times below this value were subjected to thermal treatments at 900 °C for 2 h. The patterns were maintained after the sintering process, exhibiting dense, homogeneous, and crack-free surface coatings.