Approaches for evaluating Young's and shear moduli in terms of a single SAW velocity via the SAM technique

In ultrasonic material investigations Young's modulus, E, and shear modulus, G, conventionally expressed in terms of the velocities of longitudinal (VL,) and transverse (VT) modes, are usually difficult to determine from a single measurement, in particular for scanning acoustic microscopy. Therefore, using Viktorov formula and physically acceptable approximations, we derive simple expressions for E and G in terms of the velocity, Vi, of just one propagating mode (including Rayleigh mode VR). It was found that (E, G) = (αi, βi)ρVi2. The validity of these expressions is successfully tested, analytically and graphically, for a great number of materials representing a large spectrum of densities, 1000 kg/m3 < ρ < 22 000 kg/m3, and characterized by a wide interval of velocities, 1400 m/s < VL < 12 000 m/s.