Research on detection of thickness of thermal barrier coating by laser transmission infrared thermal wave method

On the basis of the heat transfer, a one-dimensional heat conduction model was proposed. The quantitative relationship among the thickness of coating, thermal diffusivity, the slope and intercept of the surface temperature difference-frames line was established. The thermal barrier coating specimens with different thickness were used. Transmission infrared thermal wave method excited by pulse laser was adopted and thermal imager was used to collect coating surface temperature-frames curve fitting. The slope and intercept of the temperature difference-frames line were obtained by linear fitting and the thickness of coating was calculated finally. The results show that it is fairly feasible to utilize laser transmission infrared thermal wave method in rapid, non-contact and accurate measurement of thermal barrier coating thickness.