红外热波技术在热障涂层厚度检测上的应用研究

Applications of the Infrared Thermal Wave Technology in Thermal Barrier Coating Thickness Testing

为快速准确地测量热障涂层厚度,采用基于热图序列特征时间的闪光灯激励红外热波测量方法,通过建立半无限大和有限厚度两种平板传热模型,提出根据热障涂层表面温度对数曲线线性回归时间选择二阶微分曲线负峰值时间的方法,解决了采用普通帧频热像仪采集的涂层表面温度曲线二阶微分负峰较多,无法确定特征峰值时间的困难,热障涂层厚度测量相对误差小于10%,满足工程应用要求。

In order to measure the thermal barrier coating thickness efficiently and accurately,infrared flash thermography technology based on thermal image characteristic time was adopted.A method to choose the negative peak time of the second-order differential curve according to the linear regression time of the thermal barrier coating surface temperature log curve was proposed by establishing a half-infinite and finite-thickness plate heat transfer model.The problem of inability to determine the negative peak time because of multiple negative peaks of second-order differential curve using common-frame-frequency thermal imager was solved.The relative measurement error of coating thickness was less than10%and it meets the requirements of engineering applications.