Abnormalities in Ultrasonic (C-Scan) Images of Composite Structures: Impact Damaged Versus Hole Damaged

Abstract

This paper is about applying image processing to detect different types and levels of damage in composite structures using in C-scan images produced by ultrasonic testing. This method plays an important role as it can detect any discontinuities or flaws in the specimen. To analyze such critical image in an, automated inspection environment an image processing method that correlates Threshold values to Gradient Field values is used to extract important information from the c-scan images in order to detect abnormalities that may exist. The paper presents an improved approach to composite damage characterization using Threshold Level Variation as an input variable to Gradient Fields. Furthermore, the detailed results showed an important dependency between what can be detected and the used threshold level. At each level certain abnormalities appeared. Setting threshold value is proved to be a function of image type and quality, purpose and application.

Characterizing the Layer Structures of the Lacquerware From the Palace Museum by Terahertz Imaging in Reflection Geometry

“…At this time, the X-axis returns to the origin and the Y-axis moves to the next point. The same operation is repeated until the entire lacquerware is scanned [3].…”

Kompozi̇t Malzemeleri̇n Charpy Darbe Testi̇ Sonrasi Ultrasoni̇k C-Scan Yöntemi̇ İle Hasar Anali̇zi̇

“…Literatürde, çeşitli hataların ve hasarların (düşük hızlı darbe testi, üretim hataları ve gömülü kusurlar) analizi için karbon/epoksi ve cam/epoksi kompozitler başta olmak üzere birçok kompozit malzemenin incelenmesinde ultrasonik C-tarama tekniğinin kullanıldığı görülmektedir (Abdullah, 2021;Arhamnamazi et al, 2019;Hasiotis et al, 2011;Iskandarani, 2019;Santos et al, 2021;Selver et al, 2021;Tabrej et al, 2021;Tuo et al, 2019;Yolacan, 2018). Bahsedilen yöntemlerin aksine Charpy testi sonrası çoğunlukla yapı bütünlüğünün korunamaması nedeniyle sayısal modelleme ve kırılan parçaların mikroskobik görüntüleri üzerinden hasar analizi yapılmaktadır.…”