화학공학소재연구정보센터
Journal of Materials Science, Vol.29, No.23, 6241-6248, 1994
Electrochemical ZrO2 and Al2O3 Coatings on SiC Substrates
SiC was electrochemically coated with ZrO2 and with Al2O3 from 0.1 M aqueous solutions of metal-nitrate-hydrates with ethanol added. Amorphous zirconia and alumina coatings were formed with current densities from 10 to 70 mA cm(-2), and deposition durations of 1-60 min. The as-deposited coatings contained microcracks caused by drying shrinkage. Sintering of zirconia at 900 degrees C for 1 h and of alumina at 1200 degrees C for 2 h in air was accompanied by crystallization to a mixture of tetragonal and monoclinic phases in the former and to alpha-alumina in the latter. The absence of intermediate phases between the coatings and the substrates and the good adherence of the sintered coatings indicate the high-temperature stability of these coatings.