TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - nicht begutachtet (unreviewed) A1 - Rjelka, Marek A1 - Pupyrev, Pavel Dmitrievich A1 - Köhler, Bernd A1 - Mayer, Andreas T1 - Nonlinear effects of micro-cracks on acoustic surface and wedge waves T2 - Low temperature physics : an English translation of the journal, Fizika Nizkikh Temperatur N2 - Micro-cracks give rise to non-analytic behavior of the stress-strain relation. For the case of a homogeneous spatial distribution of aligned flat micro-cracks, the influence of this property of the stress-strain relation on harmonic generation is analyzed for Rayleigh waves and for acoustic wedge waves with the help of a simple micromechanical model adopted from the literature. For the efficiencies of harmonic generation of these guided waves, explicit expressions are derived in terms of the corresponding linear wave fields. The initial growth rates of the second harmonic, i.e., the acoustic nonlinearity parameter, has been evaluated numerically for steel as matrix material. The growth rate of the second harmonic of Rayleigh waves has also been determined for microcrack distributions with random orientation, using a model expression for the strain energy in terms of strain invariants known in a geophysical context. Y1 - 2018 SN - 1063-777X SS - 1063-777X U6 - https://doi.org/10.1063/1.5041442 DO - https://doi.org/10.1063/1.5041442 N1 - Original article: Fiz. Nizk. Temp. 44, 946-953 VL - 44 IS - 7 SP - 744 EP - 750 ER -