半透明材料涂层的红外检测

摘要

为了能快速、大面积检测不同基底材料上半透明材料涂层的厚度,研究了主动式红外热成像技术测量涂层厚度的方法.用脉冲可见光热源激励涂层试件表面,红外热像仪实时监控表面脉冲激励前后温度的变化.由于半透明的涂层材料吸收可见光能量不满足面吸收的条件,对其表面进行了喷涂黑漆处理.比较喷漆前后的对数温度时间变化曲线和微分对数温度时间变化曲线,并根据喷漆后的二阶微分曲线的峰值时间来测量涂层厚度.实验结果显示:半透明涂层材料表面处理后满足红外测量要求,厚度范围在0.8～1.7 mm的涂层,测量精度达0.09 mm,表明红外检测方法可以非接触、快速、大面积、定量地进行半透明材料涂层厚度的测量.%In order to measure the coating thicknesses on various substrate materials at a high speed and a large area,an active infrared thermographic technique was presented. A light pulse was used to heat to the surface of the coating and an infrared camera was utilized to capture the surface temperature change on real time. For a translucent coating, visible light could not be absorbed well on the surface,so a water-soluble black paint was painted on the surface of the coating. Compared with the differential lnT -lnt curves without painting the coating, the thickness of the painted coating can be measured according to the peak time of second differential ln T - ln t curves. Experiment results indicate that the translucent coating after painting satisfies infrared testing requirements, and the measurement precision is 0.09 mm for the thickness ranges of 0.8-1.7 mm. These data show that the infrared testing can be used in measurement of the coating thickness at high speeds,large areas,noncontact and quantification.