Ceramic oxidation coating of approximately 60 m thick was prepared on a Ly12 alloy substrate by micro-plasma oxidation in an alkali-silicate electrolytic solution. Coating thickness was measured during coating formation. The influence of current density, electrolyte temperature and inter-electrode distance on coating kinetics was investigated. Microstructure and phase compositions were analyzed. The micro-hardness of the coating was also measured. The tribological performance of the coatings was evaluated using a dry sand abrasion test. In addition, the results are compared to detonationsprayed alumina coating.