Abstract
Ultrasonic inspection plays an important role in numerous industrial fields. One of the prominent tasks is the determination of location, shape, size and orientation of defects. In isotropic materials, the location of reflectors can be inferred from time-of-flight measurements, angle of insonification and transducer position. In anisotropic media, however, such a procedure is aggrevated by several phenomena, which are the direction dependence of the ultrasonic velocities, the beam skewing effect and the modified radiation characteristics of flaws with respect to wave scattering. In this contribution, analytical relationships are presented for the scattering of ultrasound at defects in such media. Based on the mathematical formulation of Huygens’ principle, these relationships are obtained for traction-free scatterers using Kirchhoff’s approximation. Asymptotic evaluation yields explicit expressions, which are further incorporated in the Generalized Point Source Synthesis method. Numerical results are obtained for rectangular and circular reflectors, selected to compare with notches and flat-bottomed holes, respectively. Evaluation is performed in view of the radiation characteristics of these defects, considering (quasi-) longitudinal wave scattering in orthotropic composite material. Also, the elaborated relationships have been applied to calculate echo dynamic curves in dependence of transducer position for pulse-echo technique. Good comparison with experimental results has been obtained for transversely isotropic weld material.
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References
Y.H. Pao, V. Varatharajulu, ’Huygens’ Principle, Radiation Conditions and Integral Formulas for the Scattering of Elastic Waves,’ J.Acoust.Soc.Am., 59, 1361–1371 (1976)
V.T. Buchwald, “Elastic Waves in Anisotropic Media,” Proc. Roy. Soc. London, A, 253, 563–580 (1959)
J.A. Ogily, I.D. Culverwell,’ Elastic Model for Simulating Ultrasonic Inspection of Smooth and Rough Defects,’ Ultrasonics, 29, 490–496 (1991)
M. Spies, “Transducer-Modeling in General Transversely Isotropic Media Via Point-Source-Synthesis. Theory,” J. Nondestr. Eval. 13, 85–99 (1994)
M. Spies, F. Walte, “Application-Directed Modeling of Radiation and Propagation of Elastic Waves in Anisotropie Media: GPSS and OPoSSM,” in Review of Progress in QNDE, Vol. 14, eds. D.O. Thompson and D.E. Chimenti, Plenum Press, New York (1995), 1013–1020
M. Spies, M. Kröning, “Elastic Wavefield Modeling for Arbitrarily Oriented Orthotropic Media,” these proceedings
P.A. Lewis, J.A.G. Temple, G.R. Wickham, “ Elastic Wave Diffraction at Cracks in Anisotropie Materials,” in Review of Progress in QNDE, Vol. 15, eds. D.O. Thompson and D.E. Chimenti, Plenum Press, New York (1996), 41–48
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© 1998 Plenum Press, New York
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Spies, M., Kröning, M. (1998). Theoretical Evaluation of Ultrasonic Scattering by Flaws in Anisotropic Media. In: Thompson, D.O., Chimenti, D.E. (eds) Review of Progress in Quantitative Nondestructive Evaluation. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-5339-7_7
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DOI: https://doi.org/10.1007/978-1-4615-5339-7_7
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