Effect of surface layer damage on acoustic anisotropy

Data on the speeds of longitudinal and transverse waves are used to derive relations for the principal values of the damage tensor proposed. The relationship between acoustic anisotropy and the main values of the damage tensor are established. The distribution pattern of local speeds and damage along the thickness of the specimen is studied. It is shown that damage is localized in a narrow surface layer, with local damage maxima far exceeding the average damage value