Estimation of Characteristics of Nanocrystalline Layer Using the Surface Acoustic Waves

The effect of the nanocrystalline layer formed by mechanical pulse treatment on the velocity of surface acoustic waves in 65G steel samples was studied. Acoustic waves with frequencies equal to 3; 6 and 9 MHz were used. Different thicknesses of the nanocrystalline layer were obtained by the stepwise grinding method. The method of estimating the acoustic properties of the formed layer based on the velocity of surface acoustic waves in the case when the depth of wave penetration is greater than its thickness was described. An additional measurement of the nanocrystalline layer thickness was carried out using metallographic studies to determine its acoustic characteristics.