The two important acoustical parameters viz. Velocity of waves and absorption coefficient of acoustical energy propagating through a material can be used for nondestructive testing techniques to characterize the structures and materials because the frequency or temperature dependence of the acoustic loss mechanisms are well connected with structural inhomogeneities or flaws in a material. The field of material characterization and flaw detection by acoustic nondestructive evaluation thus has a broad fundamental base. This knowledge base is of great interest in that it is useful for nondestructive characterization and, particularly, to determine the effect of these inhomogeneities on the over all performance of the material. In this paper velocity and attenuation coefficient of ultrasonic waves with non-linearity parameters and average Grüneisen numbers in Vitreous Silica due to phonon-phonon interaction mechanism at temperatures between 77K-293K using measured values of second and third order elastic constants have been evaluated along <110> crystallographic direction. The results are very interesting showing some absorption kinks connected with some structural inhomogeneities characterizing Vitreous Silica at very broad temperature range.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 2, pages 771 - 774 Publisher:Ashgate Publishing Company
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