Inspection Detectability Improvement for Metal Defects Detected by Pulsed Infrared Thermography

Photonic Sensors

Wei Zhang¹  Gan Tian¹  Jietang Zhu¹  Guangjie Kou¹  Yin Li¹  Zhengwei Yang¹ 

[1] Rocket Force University of Engineering;

关键词: Pulsed infrared thermography;    metal defects;    detectability improvement;    piecewise fitting;    differential processing;   

DOI  :  10.1007/s13320-019-0489-1

来源: DOAJ

【 摘 要 】

Abstract Aiming at the drawbacks of low contrast and high noise in the thermal images, a novel method based on the combination of the thermal image sequence reconstruction and the first-order differential processing is proposed in this work, which is comprised of the following procedures. Firstly, the specimen with four fabricated defects with different sizes is detected by using pulsed infrared thermography. Then, a piecewise fitting based method is proposed to reconstruct the thermal image sequence to compress the data and remove the temporal noise of each pixel in the thermal image. Finally, the first-order differential processing based method is proposed to enhance the contrast. An experimental investigation into the specimen containing de-bond defects between the steel and the heat insulation layer is carried out to validate the effectiveness of the proposed method via the above procedures. The obtained results show that the proposed method can remove the noise, enhance the contrast, and even compress the data reaching at 99.1%, thus improving the detectability of pulsed infrared thermography on metal defects.

【 授权许可】

Unknown