The present study introduces two quantitative parameters to compare the accuracy of ultrasonic C-scan testing and X-ray radiography methods in the damaged area detection under low-velocity impact in polymer-based composites. For this purpose, the hand lay-up technique of composite processing was employed to prepare the composite specimen. A composite specimen consisting of the glass fiber reinf...

In general the ultrasonic testing is used for flaw detection and localization in tested materials. Flaws in materials are commonly characterized in measured ultrasonic signals by faults echoes. Ultrasonic signals measured on materials with coarse grained structure contain relative high level of noise. This undesirable part of ultrasonic signal should be reduced to make the fault echo detection ...

In non destructive testing of materials, the ultrasonic imagery is a field in full rise. Indeed , more than one convivial representation of the results , the operations of detection , localization and sizing of the defects can be carried out automatically by the analysis of synthesized images. The problem breaks up in general into a phase of preprocessing to only limit the quantity of informati...

In this paper, quantitative evaluation of ultrasonic Cscan images through estimation of their Fractal Dimension (FD) is discussed. Necessary algorithm for evaluation of FD of any 2-D digitized image is implemented by developing a computer code. For the evaluation purpose several C-scan images of the Kevlar composite impacted by high speed bullet and glass fibre composite having flaw in the form...

This paper presents the in-house development and application of a C-scan ultrasonic facility ULTIMA 200M2 at the Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, carried out in collaboration with the Electronics Division, Bhabha Atomic Research Centre (BARC), Mumbai. The paper describes various constituents of the system developed and also highlights the typical results obtained usi...

In this paper an alternative way of generating C-scan images using Fractal Dimension (FD) of any digitized waveforms as an ultrasonic feature is proposed. The work is carried out on the composite specimen having flaw in the form of inclusion and damage created by the drop weight impact. The technique to estimate FD of a 2D image is modified in this work and a procedure to compute FD of a digiti...

A C-scan imaging facility has recently been added to the ultrasonic system in use at Moorfields Eye Hospital, London. The technique is explained and typical C-scans are presented to demonstrate the normal orbital fat and optic nerve, together with selected pathological conditions in the orbit. The C-scan facility permits imaging of the orbital contents in the coronal plane. This coronal plane i...

Ultrasonic inspection has been widely used to detect defects in composite materials such as internal discontinuity, cracks, delaminations, inclusions, lack of bond etc. However when the bonded specimen has small thickness, the echo from the defect region makes it difficult to identify the echo from the unflawed· region. To overcome these disadvantages, different statistical pattern recognizing ...