Method of making mixed metal oxide coated substrates

摘要

In a reactive ion plating process utilizing radio frequency power, the rate of evaporation of a noble metal such as ruthenium or iridium, the rate of evaporation of a valve metal such as titanium, and the partial oxygen pressure are adjusted to produce electrically conductive mixed metal oxide ceramic coating on a valve metal substrate. The noble metal constitutes 10-20 percent of the metal atoms in the coating. The coated substrate can sustain 150 amperes per square meter of exposed coating surface in fresh water electrolyte for at least 20 hours, and preferably at least 75 hours, without an excessive increase in the voltage level required to maintain that current density.