Effect of Heat Treatment on Oxide Coatings Deposited by Hybrid Aerosol Deposition

The utilization of super thermal field created by a laser or high-intensity energy is attracting to realize new materials development. However, it requires the deep understanding of material transformation upon laser irradiation. Especially, in case of ceramic coatings, a simple laser irradiation can cause rapid quenching of molten materials during cooling stage, which results in the generation of cracking. Therefore, the use of laser is not simple. In order to realize it, the role of heating should be clarified and examined in detail as the first step. In this study, the effect of heat treatment on the oxide ceramic coatings deposited by the hybrid aerosol deposition (HAD). Alumina was deposited by HAD. The obtained coatings were heat-treated by a furnace at elevated temperatures. In case of alumina, a clear color recovery was observed at 1200 ˚C. The evolution of microstructure and mechanical properties with temperature and time will be described. Preliminary result of rapid thermal annealing will also be presented and discussed in comparison to that of furnace heating.