Laser Chemical Vapor Deposition of Thick Oxide Coatings

Thick oxide coatings have wide-ranged applications typically thermal barrier coatings. Although high speed deposition processes, often plasma spray or electron-beam physical vapor deposition, have been employed for these applications, another route has been pursued to improve the performance of coatings. We have proposed laser chemical vapor deposition (LCVD) for high-speed and thick oxide coatings. Conventional CVD can fabricate coatings at deposition rates of several to several 10 μm/h, and conventional LCVD has been mainly focused on thin film coatings and low temperature deposition. In the present LCVD, high-speed deposition rates ranging from 300 to 3000 μm/h have been achieved for several oxide coatings such as yttria stabilized zirconia (YSZ), TiO2, Al2O3 and Y2O3. This paper describes the effect of deposition conditions on the morphology and deposition rates for the preparation of YSZ and TiO2 by LCVD.