TRANSFORMATION AND SCATTERING OF SURFACE WAVES ON THE ACOUSTIC LOAD TO ULTRASONIC EVALUATION AND MEASUREMENTS. Part 1. The boundary of acoustic contact is sliding

for the enhancement and improvement of ultrasonic methods evaluation and measurements. The purpose of this work is to determine the influence of the geometric parameters of the acoustic load body and its position on the coefficients of reflection and propagation of the Stoneley and Rayleigh waves and to identify the possibility of using the results of the study for practical applications.

Based on the analysis of the acoustic path and the experimental data, the relationship between the measured amplitude parameters and the coefficients of the propagation and reflection of surface waves, as well as the reflectivity of the contact region of the load body in the form of a prism through the sliding boundary, which reaches up to ≈ 32–34 дБ, is established. For the first time, the dependence of these coefficients on the inclination angle of one of the prism lateral faces in the range of 0 ± 45°, dimensionless thickness of the contact layer (0–0,05) and its orientation relative to the acoustic axis.

It is established that these coefficients are mainly maximal when the prism is rectangular. The coefficient of reflectivity in the hard contact of bodies is more than an order of magnitude less, and the coefficients of wave propagation – comparable in magnitude. The prospects of using the results of the study to evaluate the quality of adhesion of materials during welding, soldering, gluing, detection of defects in hardto-reach places, as well as to determine the physical and mechanical properties of metals by the proposed method of creating a reference signal are shown.

1. Kruger S.E., Bakker A.J. Detection of kissing bond in extruded aluminum by laser-ultrasound. Review of Progress in Quantitative Nondestructive Evaluation, 2007, vol. 27A, pp. 279–285.

2. Pecorary C. Nonlinear interaction of plane ultrasonic waves with an interface between rough surfaces in contact. JASA, 2003, vol. 113, pp. 3065–3072.

3. Kim H.J., Song Golden S.J., Kim D.Y., Kwon S.D. Evaluation of thin coating layers using Rayleigh-like waves. Review of Progress in Quantitative Nondestructive Evaluation, 2007, vol. 27B, pp. 1066–1073.

4. Baev А.R., Sergeeva O.S., Asadchaya M.V., Konovalov G.Е. [Propagation of Rayleigh waves in solids with protrusion]. Devices and methods of measurements, 2011, vol. 2, no. 2, pp. 121–129 (in Russian).

5. Jerzak W., Siegman. W.L., Collinz H.D. Modeling Rayleigh and Stonely Waves and other Interface and Boundary Effects with the Parabolic Equation. JASA, 2005, vol. 117, pp. 3497–3503.

6. Aladeddin E., Tchambaz H., Al-Adani N. Combining NMR and Stonelyn Analysis for Better Estimation and Permeability in Carfonate Reservoirs. Paper E. Proceedings, Formation Evaluation Symposium of Japan Society Petrophysist and Well Log Analysitst, Japan, 2005, Chapter, 7 p.

7. Baev А.R., Sergeeva O.S., Asadchaya M.V., Tishchenko M.A.: Ultraszvukovoye ustroistvo s otraza-telem poverchnostnykh voln [Ultrasonic arrangement with refl of surface waves]. Patent RB no. u20130571, 2014.

8. Аbbakumov К.Е., Konovalov V.A. [Influence of the broken acoustical contact on propagation of Stonely waves at the boundary of solid mediums]. Defectoscopiya [Defectoscopy], 2008, no. 3, pp. 52–58 (in Russian).

9. Abbakumov K.E., Konovalov V.A. Britvin Informative opportunities of wave processes at the boundary of solid mediums in conditions of broken acoustic contact. Abstracts of 10th European conference on Nondestructive testing, Moscow, 2010, pp. 173–175.

10. Lutkevich A.M., Zukove A.V., Samokrutov А.А., Shevaldykin V.G. [Acoustical fields of the probes with small aperture. Transverse waves, radiated by rectangular source of the normal force]. Kontrol. Diagnostica [Control. Diagnostics], 2004, no. 4, pp. 3–8 (in Russian).