Infrared Polarization Imaging-based Non-destructive Thermography Inspection

TL;DR

This paper introduces a novel infrared polarization imaging technique for non-destructive testing that enhances defect detection accuracy by leveraging polarization characteristics of infrared radiation, especially when intensity differences are minimal.

Contribution

The study proposes and validates an infrared polarization imaging-based NDT method, demonstrating improved detection detail and accuracy over traditional intensity-based methods.

Findings

Infrared polarization degree varies regularly with thermal environment changes.

The proposed method effectively detects defects in different materials.

Experimental results confirm the method's improved detection performance.

Abstract

Infrared pulse thermography non-destructive testing (NDT) method is developed based on the difference in the infrared radiation intensity emitted by defective and non-defective areas of an object. However, when the radiation intensity of the defective target is similar to that of the non-defective area of the object, the detection results are poor. To address this issue, this study investigated the polarization characteristics of the infrared radiation of different materials. Simulation results showed that the degree of infrared polarization of the object surface changed regularly with changes in thermal environment radiation. An infrared polarization imaging-based NDT method was proposed and demonstrated using specimens with four different simulated defective areas, which were designed and fabricated using four different materials. The experimental results were consistent with the simulation results, thereby proving the effectiveness of the proposed method. Compared with the infrared-radiation-intensity-based NDT method, the proposed method improved the image detail presentation and detection accuracy.