TY - CHAP U1 - Konferenzveröffentlichung A1 - Gartsev, Sergey A1 - Rjelka, Marek A1 - Köhler, Bernd A1 - Mayer, Andreas T1 - Determination of the nonlinear elastic constants in a surface treated layer for aero-engine disk residual stress measurement T2 - 10th International Symposium on NDT in Aerospace N2 - Existing ultrasonic stress evaluation methods utilize the acoustoelastic effect for bulk waves propagating in volume, which is unsuitable for a surface treated material, possessing a significant variation in material properties with depth. With knowledge of nonlinear elastic parameters – third-order elastic constants (TOEC) close to the surface of the sample, the acoustoelastic effect might be used with surface acoustic waves. This work is focused on the development of an independent method of TOEC measurement using the effect of nonlinear surface acoustic waves scattering – i.e. the effect of elastic waves interaction in a nonlinear medium. In this paper, the possible three wave interactions of surface guided waves and bulk waves are described and formulae for the efficiency of harmonic generation and mode mixing are derived. A comparison of the efficiency of surface waves scattering in an isotropic medium for different interaction types is carried out with the help of nonlinear perturbation theory. First results for surface and bulk wave mixing with known second- and third-order elastic constants are shown. Y1 - 2018 UR - https://www.ndt-aerospace.com/portals/aerospace2018//proceedings/Fr.1.A.4.pdf N1 - Es handelt sich um einen Beitrag zu den Verhandlungen der Tagung 10th International Symposium on NDT in Aerospace, https://www.ndt-aerospace.com/Programme (unter Fr.1.A.4) SP - 8 S1 - 8 ER -