As applications of thermal spray processes are expanding, the importance of computer-aided design systems and computer-aided engineering systems for these processes has been growing. The principal objective of this study is to propose a new analytic method for the prediction of coating thickness and deposition efficiency. This method is called the particle tracing method and is based on the Monte Carlo simulation method. In order to evaluate the validity of this model, several tests were carried out. The same stainless steel 316L layers coated by the HP/HVOF process (TAFA JP-5000) were used throughout each test. First, spray patterns were observed which had formed on flat-plate specimens from various spray gun angles. Coating thickness distributions on several curved planes were consequently investigated. Finally, the coating process for a blade of a compressor in a gas turbine was simulated. In the right of the results of these experiments, it is summarized that the calculated values of the coating thickness obtained by our method are in good agreement with experimental values. The accuracy is within 10% of the maximum thickness value in each specimen, except for at the edge of the work-piece. In conclusion, the particle-tracing method can be applied to the fundamental analytic model in the CAD or CAE system for thermal spray processes.

Thermal barrier coating (TBC) is a technology for preventing the rise in surface temperature of the metal substrate by coating a ceramic with low thermal conductivity for the hot section components such as blades, nozzles and combustion chambers. In this paper, for some types of thick TBC specimen which had zirconia based ceramic top coat of 600 micrometer in order to improve the thermal insulation performance, thermal cycle property and heat flux are examined by using thermal simulating facility by gas burner heating. The paper also discusses fracture mechanism of the thick TBC. Paper includes a German-language abstract.