在传热学的基础上建立涂层试样的一维热传导模型, 确立了涂层厚度与表面温度差值-帧数直线的斜率、截距以及涂层热扩散率之间的定量关系。以不同厚度的热障涂层试样为例, 采用新型脉冲激光透射法激励, 对热像仪采集到的不同激励功率下涂层表面温度差值-帧数曲线线性拟合, 求得拟合直线的斜率和截距值, 最后计算得到热障涂层厚度值, 结果表明: 激光透射法红外热波检测技术能很好地应用于热障涂层厚度的快速、精确、非接触检测。

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.