连续太赫兹成像系统对多层蜂窝样件无损检测的实验研究

Experimental research on nondestructive inspection for multilayer cellular samples using continuous terahertz waves imaging system

太赫兹无损检测作为一种新型技术,已经成为X射线和超声无损检测技术的有力补充。太赫兹连续波成像技术可以进行实时成像,其扫描速度和成像质量都能满足太赫兹无损检测的要求。本文利用连续太赫兹成像系统对多层蜂窝样件进行了检测,得到了样件不同纵深处的二维太赫兹图像。测试结果表明该系统能测试样件内部每一层中夹杂异物的位置、分布情况及轮廓,并能对异物的基本属性做出判断。本研究为太赫兹连续成像系统用于航空、航天、电子等样件的无损检测提供了有借鉴意义的案例。

Nondestructive inspection is an emerging technique which can be conducted directly in the testing ground with no damage to the parts or materials. Now it has been widely used in evaluating the quality of samples. Because of the characteristics of low energy,high signal to noise ratio （SNR） of the time-domain spectroscopy,terahertz （THz） waves play an important role in nondestructive testing. Con- tinuous terahertz waves imaging systems provide us a novel way for nondestructive inspection. Using such a system, a multilayer cellular sample has been inspected and the two-dimensional terahertz images in different layers of the sample are obtained. The results indicate that the location, distribution, outlines and properties of the inclusions in the sample can be inspected by the system. Our research provides a reference case for continuous terahertz imaging systems used as nondestructive inspecting devices in aviation, aerospace, electronics and other fields.