再制造喷涂层界面结合性能脉冲红外热像评估技术

针对再制造工程中常见的喷涂层界面结合性能评价问题,采用脉冲红外热像技术对3Cr13合金涂层的界面脱粘缺陷进行检测评估。以信噪比(SNR)为评价标准,对比了两种不同热图序列处理方法在预处理和后处理阶段的效果。结果表明:在预处理阶段,基于表面热信号的多项式拟合算法(PF)将原始热图的信噪比由5.34提升到9.61,其效果优于基于单张图像中值滤波算法(MF);而在后处理阶段,基于单张图像的主成分分析法(PCA)对缺陷特征的表征比基于表面热信号的脉冲相位法(PPT)更加准确,第三主成分重建热图的信噪比达到17.99。综合而言,基于单张图像的热图序列处理方法在再制造喷涂层界面结合性能评价中具有更好的效果。

Interfacial Adhesion Performance Assessment of Remanufacturing Spraying Coatings by Pulsed Thermography

Aiming at the interfacial adhesion performance assessment of spray coatings, which was common in remanufacturing engineering, interface debonding defect of the 3Cr13 coating was detected with pulsed infrared thermography. Taking the signal to noise ratio (SNR) as criterion, two different image processing methods were compared both in the pretreatment and post-treatment stages of thermal image sequence. The results show that in pretreatment stage, SNR is improved from 5.34 to 9.61 with the signal-based algorithm polynomial fitting (PF), which is better than the image-based median filtering (MF) algorithm. In post-processing stage, the image-based principal component analysis (PCA) algorithm extracts more precise defect feature than the signal-based pulse phase thermography (PPT), and the SNR reaches 17.99 on the thermal image, which is reconstructed with the third principal component heat map. In a word, the image-based processing algorithms achieve a better result than the signal-based processing algorithms in the evaluation of interfacial adhesion performance of remanufactured sprayed coatings.