Ultrasonic Determination of Elastic Constants from Oblique Angles of Incidence in Non-Symmetry Planes
The most common technique to determine the elastic constants of anisotropic materials from ultrasonic wave speed measurements requires that the material be cut into samples such that particular symmetry directions can be accessed for normal incidence wave speed measurements.[1,2] This is a destructive technique and is not feasible for thin or inhomogeneous materials. A truly nondestructive technique is needed. Recent work along these lines has addressed composite materials using ultrasonic immersion techniques.[3–7] However these methods have been limited to measurements in symmetry planes. Due to this limitation, all of the elastic constants can not be obtained by this technique alone. Two of the limiting factors are: the lack of a general analytic closed form solution for elastic wave propagation in anisotropic materials and that the energy vector does not, in general, lie in the plane formed by the incident wave and the refracted phase velocity. However, general analytic closed form solutions have been recently reported, removing the first of the limitations.[8,9] The second limitation greatly complicates the analysis of the problem.
KeywordsElastic Constant Incident Beam Anisotropic Material Circular Cone Phase Vector
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- 2.R.D. Kriz and V.V Stinchomb, Experimental Mechanics, 19, 41 (1979).Google Scholar
- 5.R. Kline, Materials Eval., 46, 986 (1988).Google Scholar
- 6.L.H. Pearson and W.J. Murri, Rev. Prog. Quantitative NDE Vol. 6B, Eds. D.O. Thomson and D.. Chimenti, ( Plenum 1987 ) p. 1093.Google Scholar
- 9.R.B. Mignogna, Rev. Prog. Quantitative NDE. Vol. 8A Eds. D.O. Thomson and D.E. Chimenti, ( Plenum 1989 ) p. 133.Google Scholar