Abstract
Several new techniques in composite material testing using ultrasonic guided waves are discussed in this paper, including both theoretical and experimental studies. Our numerical simulation tool, integrated with the semi-analytical finite element technique, global matrix technique and normal mode expansion technique, together provides a detailed understanding of guided wave propagation and excitation characteristics. Based on understanding the wave propagation and excitation, guided wave modes with unique performances are used in experiments. The air-coupled ultrasonic scanning system is suitable for fast testing of damage in composite plates. The result of the guided wave scanning system shows a damage detection and localization capability which is comparable to the ultrasonic C-scan system, but with a much faster test speed. As a structural health monitoring approach, a guided wave tomographic technique for composite structures was developed. The tomographic images can be obtained by using the guided wave signals taken by a piezoelectric leave-in-place sensor network. The locations and sizes of the discontinuities can be directly observed from the images. Ultrasonic guided wave phased array technology has great potential in structural health monitoring. The guided waves can be preferably excited in a certain direction and thus the penetration power can be improved. Although the guided wave phased array is much more complicated in composites, it is still possible, with a solid understanding of guided wave mechanics, to achieve excellent results.
Original language | English (US) |
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Pages | 801-805 |
Number of pages | 5 |
Volume | 65 |
No | 8 |
Specialist publication | Materials Evaluation |
State | Published - Aug 2007 |
All Science Journal Classification (ASJC) codes
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering