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shown that the presence of a depth leads to a significant error in the measurement of

velocity, which is caused by the passage of an acoustic wave through the layer of

contact fluid, which is formed when the surface of the control object and the contact

area of the converter are not parallel. The influence of the depth on the time delay of

the acoustic signal using different types of contact fluids has been investigated. A

method for estimating the magnitude of the error in determining the SAW velocity

caused by the presence of depressions is proposed, which is based on measurements

using contact fluids with different acoustic wave velocities.

A technique has been developed for a converter with rigidly coupled excitation

and receiving prisms for determining the speed distribution of the SAW, which

combines the ability to change the measurement step with no need to determine its

magnitude with high accuracy. It is shown that the contribution of the error of

determining the displacement of the converter to the error of determining the velocity

depends on the magnitude of the change of velocity in the adjacent areas and is equal

to the product of the error of determination of the displacement of the converter by

the magnitude of the relative change of these velocities. The use of the proposed

approach allows to determine the rate of SAW in one area of the sample relative to

another. The technique created allows us to optimize the step of measuring the SAW

rate for non-uniform objects of control.

The criterion for selecting the optimal value of the measurement step to

determine the distribution of the SAW rate in non-uniform objects of control is

formulated. According to the proposed criterion, the selection of the measurement

step is made on the basis of the properties of the control object and the characteristics

of the measuring equipment. We also propose an algorithm by which you can select a

measurement step that meets the stated criterion.

A technique for measuring the velocity of acoustic waves was developed based

on the use of a continuous reference signal with the frequency of excitation of an

acoustic wave and a comparison of the passage time of an acoustic wave in the

studied object of control and a comparison sample. The technique allows the use of