针对涂层下金属的腐蚀损伤不易被观察到而造成的安全隐患问题,制作了防腐涂层下的材料腐蚀模拟试件,应用红外热波技术进行检测,得到试件表面温度分布热图像,并在腐蚀区域和正常区域中取点,采集到相应区域的温度变化曲线和温差曲线.结果表明,红外热波方法对涂层下的腐蚀损伤具有较好的检测效果,腐蚀损伤区域和正常区域的表面温差达到最大的时刻是最佳检测时间,可用于估算涂层厚度.通过对典型时刻热图的处理,可实现腐蚀损伤大小和位置的定量识别,但检测结果受材料表面的均匀度影响较大.
Infrared thermal wave technology was employed to detect the corrosion damage under coating, which could not be easily observed and caused safety problem. The infrared thermal images of surface temperature distribution on the tested specimen were captured, as well as the surface temperature history of areas with and without pre-corrosion damages, and there with the temperature difference of the two areas. Analysis of the test results showed that the infrared thermal wave technology was an effective tool in detecting corrosion damage under coating. The optimum detection moment for estimating the coating thickness and position and size of damages was when the temperature difference between corrosion area and sound area reached the maximum. The damages could be quantitatively recognized by images processing, but surface uniformity of the specimen had great impact on the damage identification.