Том 52, № 7 (2016)

The sensitivity of Lamb waves and SH-waves to changes in elastic properties has been studied in different parts of dispersion curves. We demonstrate methodological peculiarities of using these waves for assessing the anisotropy of sheet iron with regard to the selection of frequency range and wave mode and an allowance for the scale factor of anisotropy. Distinctive features of the suggested technique are presented.

A special technique is proposed for processing detected signals. The technique uses an adjustable orthonormal basis and makes it possible to effectively identify defects by monitoring the structure and peculiarities of surface wave fields.

Expansion of the application domain and heightened requirements for the accuracy of acoustic-emission (AE) testing have necessitated the optimization of AE-based nondestructive strength-testing techniques. Current trends in the development of these techniques are provided and general principles for improving their efficiency are stated. Examples of the implementations of AE testing on various objects are illustrated.

An exact solution for a linear problem of magnetostatics about an infinite cylinder with an infinite noncoaxial cylindrical flaw has been derived in the system of plane bipolar coordinates under the condition that external magnetizing field remains unchanged along the length axis of this model body. The solution has been tested for theoretical veracity and compared with the solution of a similar problem that was obtained by one semianalytic method [2]. For a particular problem about a halfspace with an infinite cylindrical flaw, an exact solution has been obtained and compared with results that were achieved by other methods. The mismatch between the solution of the problem about a halfspace and the solution of the problem with passage to the limit of a half-space has been considered. An algorithm is described for solving the inverse problem of separate determination of flaw depth and dimensions.

Calculations of a dedicated optical system for the quality inspection of cylindrical surfaces are presented. Peculiarities of imaging a cylindrical surface by means of specially enhanced inherent field curvature are considered. Results of using the system for the inspection of quality of fuel pellets are provided.