الفهرس | Only 14 pages are availabe for public view |
Abstract Nondestructive testing (NDT) of adhesive bonded joint is of atmost importance in the production of reliable structures in different fields of industry. In this work a review of the different methods of NDT has been made, and it has been concluded that ultrasonic testing is the most versatile and practical method. A coding system has been developed to describe all signals reflected from a laminated bonded joint. This coding system has been used to develop a computer program which predicts the signal wave-form to be expected on the instrument CRT at ideal conditions. The obtained wave-form could be used for comparison with the actual received signal, thus enabling quick recognition of any defect. Different methods of ultrasonic testing have been investigated. The amplitude method has been proven practical only in testing layered material with small differences in acoustic impedence. However, when the difference in acoustic impedences of the two materials has been large, this method has been proven impractical. The phase reverse method, which requires an instrument with RF-mode has been investigated. It has been found as the most suitable method in the case when detecting bonded joint flaws showing slight differences in their echo amplitudes. |