复合材料红外无损检测的建模分析和热像处理

Modeling and image processing in infrared thermographic NDT of composite materials

红外热成像无损检测由于检测面积大、速度快和非接触从而在复合材料缺陷检测中的应用越来越广泛 .对碳纤维增强塑料的红外热成像无损检测从数学建模和热像数据处理 2个方面作了研究 .针对含有teflon夹片的碳纤维增强塑料试件的红外无损检测实验中出现的缺陷表面温差信号为负的“非传统”现象提出了新的数学模型 ,作了仿真计算 ,解决了常规模型预测结果与实验结果之间的矛盾 .应用5种国际上流行的热像数据处理方法对实验数据进行了处理 ,并对各种处理方法用统计方法作了比较 。

Infrared thermographic nondestructive testing(NDT) was increasingly used in the inspection of composite materials due to large surface, rapid and noncontact testing capability. The modeling and thermal image processing of the NDT for carbon fiber reinforced plastic (CFRP) were researched. A mathematical model was proposed for the CFRP reference samples with Teflon inserts, and the simulation was carried out. The causes of the phenomenon that the temperature on defects appears lower than that on the background were analyzed. Many advanced data processing methods in the inspection of CFRP samples were used to deal with the infrared image sequences. Several processing algorithms were statistically evaluated to demonstrate that the Fourier transform and the correlation technique can provide the highest values of signal-to-noise ratio.