基于红外锁相法的涂层脱粘缺陷检测与识别

Detection and Recognition of the Debonding Defect of Coating Based on Lock-in Thermography

通过建立涂层的三维非稳态导热模型,对涂层脱粘缺陷模型的正弦调制加热过程进行了数值计算。在不同涂层厚度与缺陷尺寸下,分别提取缺陷中心处与无缺陷处表面温度相位并进行差值计算;沿缺陷半径方向均匀取点,并对涂层表面平均温度曲线进行一阶差分。研究结果表明:通过缺陷处与无缺陷处相位差可有效检测缺陷,通过温度一阶差分可对缺陷进行定量识别。

In this paper, the 3D unsteady heat conduction model of coating is established, and the sinusoidal modulation heating process of the debonding defect model of coating is analyzed numerically. The phase of temperature changes on coating surface of defect center and no defects are extracted respectively and the difference with different coating thickness and defect size is calculated. First order difference is used for the processing of average temperature curves of coating surface which were extracted along the defect radius direction. The results show that coating defect could be detected and recognized well by phase difference and the first order difference of temperature.