Том 53, № 9 (2017)

Research into applications of acoustic SH-waves and Love waves to nondestructive testing of stratified media is reviewed. A mathematical model has been developed for describing the propagation of waves with horizontal polarization (SH-waves and Love waves) in anisotropic (monoclinic) stratified media. A modified transfer-matrix method (TM-method) has been developed in order to obtain the solution. Noncanonical-type waves with horizontal transverse polarization have been studied. The dispersion curves have been obtained for a multilayer composite that is in contact with an anisotropic semi-infinite space. It has been shown that the physical characteristics and geometry of any internal layer can be determined based on changes in the dispersion curves.

Flaws that occur due to the following processes involved in the production of electronic components have been examined: soldering of crystals to pack bases; assembly of flip-chips; and sealing of integrated circuits with a plastic. The analysis has been performed by scanning acoustic microscopy.

Comparative analysis of the effect that the pre-history of plastic deformation by uniaxial tension has on the regularities in the behavior of some magnetic parameters of metal in different zones of a welded large-diameter pipe made of strength grade X70 steel has been carried out under the conditions of subsequent elastic uniaxial tension (compression).

Most metals endure in contact with ambient air, liquids or other metals the phenomena of oxidation. The kinetics of the corrosion can be significant and destroy the metal. The marine corrosion or soil affects many materials, more than ever if it touches the pipeline, ship hulls or buried pipes. The investigation of NDT methods to predict corrosion behavior can be a rational solution to prevent from this kind of industrials problems.Eddy current and pulsed eddy current (PEC) are proposed as a powerful Nondestructive Testing and Evaluation (NDT&E) technique. The application of this kind of technique in the industrial domain is used in detection of the defects, particularly in the determination of corrosions information contained in the received signal gives the possibility allow to use the PEC in the Non Destructive Evaluation of materials that can be analysed. The work in this papers explain the behaviour of the eddy current, pulsed Eddy Currents and various electromagnetic parameters in the analysed samples. We have showed in this work that all microstructure modifications of the samples were detected and can be quantified by Pulsed eddy current measurements. Modifications of the microstructure obtained by air cooled, quenched and corroded samples in aluminium, heat treatment changement in mild steel were evaluated by PEC.

The problem of improving the accuracy and extending the range of geometrical measurements taken by video endoscopes equipped with attachable stereo adapter has been considered. For calibration and measurements, it has been suggested to use a ray tracing model of stereoscopic recording that takes the actual paths of rays in the prism into account. Based upon multiple experiments with test objects, it has been shown that this allows one to reduce the error in measurements of linear dimensions (length and depth) and area. The theoretical conclusions have been confirmed by results obtained when measuring defects in the blades of a jet engine with the use of a real stereoscopic video-endoscopic system.

A nonstationary gas flow in the piping of a compressor station at the entrance to a gas pipeline has been considered. Factors that affect the emergence and development of gas flow pulsations that result in hazardous low-frequency pipeline vibrations have been studied. A mathematical model of the process is described. The system of acoustic-approximation equations is used that makes it possible to allow for the tree-type topology of pipeline network in the booster part of a compressor station, with 90-deg pipe turns, the presence of obstacles in the form of shut-off and control valves, and pipeline pitch being disregarded.