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The article describes a hardware and software complex designed for defectoscopy and study of material properties. Sections of high-strength steel 08G2B pipes were scanned in the course of the research. The purpose of this study is to determine dependency of eddy current sensor signal and mechanical and operational properties of the base metal (K65 steel grade) and demonstrate the ability of developed eddy current probe to detect continuity defects and corrosion in this type of metal. The steel is ultra-low-carbon, which makes it possible to study their properties using the eddy current method. The eddy current method is a non-contact one being used both for cracks identification and determination of their characteristics. A special superminiature eddy current probe was developed, which includes three coils - stabilizing, measuring and exciting. The coils were placed on a pyramid-shaped core made of alloy 81NMA. The eddy-current transducer runs under the control of the developed hardware-software complex with a system for suppression of noise and amplification of signal received from the eddycurrent transducer. Signal processing makes it possible to separate the effects of closely spaced cracks on the eddy-current transducer signal and evaluate the contribution of each crack separately. As a parameter containing information about the presence of defects in the object of control, the voltage arrived at the measuring coil of the eddy current probe signal was used. The work studied sections of pipes with model continuity defects – cracks and holes. A research that allows to simulate the presence of corrosion in the metal was also conducted. The extreme values of the eddy current probe signal over defects of different types are obtained at various velocity, that allows to identify the type of defect, while changing the frequency of the signal on the probe allows to determine the depth of the defect.

High strength aluminum alloys are particularly suitable as lightweight materials in vehicle and aircraft engineering. The wear resistance of materials can be improved by surface and coating technology. Strengthening of parts and units of machines, increased reliability and longer service life is an important task of modern industry. The aim of research was to apply boride coatings on surface of steel parts. Timeliness is subject to necessity to harden surface of steel used in high-load conditions. Samples of coatings on 65 G grade steel, applied by HFC-heating, were obtained. Research of samples with different coatings by means of metallurgical microscope was carried out. Data on samples with different coatings research by means of an eddy current measuring system was obtained and conclusion on electrical conductivity distribution along the sample surface depending on flux quantitative content during boriding was made.

The research aims to develop a microminiature converter for electrical steel investigation. The research topic is considered relevant due to the need for evaluation and forecasting of safe operating life of electric steel products. The authors determined the capability to study steel characteristics at different depths based on variations of eddy-current converter amplitude at the steel-dielectric boundary. A microminiature transformer-type converter was designed, which enables to perform local investigations of ferromagnetic materials using eddy-current method based on local studies of the steel electrical conductivity. Having the designed converter as a basis, a hardware-software complex was built to perform experimental studies of steel at the interface boundary. A system was developed for automated converter relocation above the studied object at a specified velocity. Test results are reported for a specimen with continuous and discrete measurements taken at different frequencies. Response dependence of eddy-current converter was found to demonstrate non-linear behavior at steel to dielectric transition. The effect of gap between the eddy-current converter and the test object is investigated.

On the basis of an eddy-current transducer of a transformer type, a measuring system is made, which makes it possible to estimate the possibility of using the eddy current method for measuring the thickness of conductive and dielectric coatings placed on a conductive base. The purpose of this work was to evaluate the possibility of using only an amplitude eddycurrent method for determining the thickness of a conductive or dielectric coating on a conductive base and estimating the error of such measurements. The design of the measuring system and measurement techniques is described. The article presents data demonstrating the dependence of the amplitude part of the signal on objects of different thicknesses; limiting object dimensions at which these measurements are expedient are experimentally established.

Based on the eddy current transducer of the transformer type, a measuring system has been developed that makes it possible to investigate the welded joints obtained by friction stir welding (FSW). The main technical information about the eddy current converter being used is given, and a measurement procedure is described that allows to search for defects in welded seams of aluminum plates. The device allows to automatically change the main operating frequency of the device and the cutoff frequency of the filtration system. The experiments were carried out on aluminum-magnesium alloy plates being connected by friction welding. In the article, the results of measurements are presented, allowing to estimate the quality of a welded seam and to answer a question on reliability of welding.

Aluminium has a reputation for ease of use, strength and durability. In addition to its exceptional aesthetic properties, solid aluminium does not burn. As architects, contractors, consultants and real estate owners look to meet stringent safety requirements in the construction and refurbishment of high-rise constructions for both residential and commercial uses, aluminium cladding provides an alternative that is not only safe but that is also durable and attractive. One of the ways to connect elements into a aluminium construction is welding. friction stir welding is one of the most efficient. The authors developed a measuring system based on subminiaturized eddy-current transducers aimed at examining locally the defects of welded joints in aluminium-magnesium alloy plates connected by means of friction stir welding. The authors made a modification of the Delyann filter, which allowed them to increase considerably the signal-noise relations. The dependency of the eddy-current transducer response on defects was provided, i.e. concealed cuts and openings inside the welded joint, at the frequencies of 100-10000 Hz of the exciting winding.

A new gage system was made based on the eddy-current transducer. The system makes it possible to evaluate the possibility of using the eddy current method to measure the thickness of conductive and dielectric coatings applied on a conductive base material. One of the important advantages of the developed gage system is the possibility of local measurement of the thicknesses of conductive and non-conductive coatings. In this article, in particular, the measurement features are described in detail, as well as the specificity of the gage system. Also it represents data, showing the dependence of signal amplitude on objects of different thicknesses, and experiments proved the limiting dimensions, at which measuring data are useful.

The measuring system based on subminiature eddy-current transducers has been developed to carry out local investigations of aluminum-magnesium alloy plates for flaws. The Delianna filter has been modified to allow the significant increase of signal-to-noise ratio. A scheme that uses a computer as a generator and receiver of signals from windings is proposed. It is capable of automatically changing the filtering cutoff frequency and operating frequency of the device. The transducer has been tested on a number of aluminum-magnesium alloy plates with flaws. The article presents data on the relationship of eddy-current transducer response to the presence of flaws in alloys as hidden holes at signal frequencies comprised between 300÷700 Hz on an exciting winding.

The eddy current transducer (ECT) of the transformer type is used to construct a sensor for investigating titanium sheets joined by a welded joint. The characteristics of the ECT are presented. The measurement method for controlling the occurrence of defects in the welded joints in titanium alloys is described. The experimental results obtained by the ECT on two welded titanium sheets are presented. The depth of penetration of the field of eddy currents into the investigated object is determined and the dependences describing the response of the ECT at different depths of the defect are outlined. The relationships can be used for evaluating the quality of welded joints and determining the reliability of welding.

This article analyzes modern theoretical and conceptual models of social anxiety disorder (SAD) (cognitive, metacognitive, psychopathological) with a view to determine specific features of psychological mechanisms of disorders studied in various approaches, to identify similarities and differences in conceptual SAD models, their heuristic specifics and efficiency in the diagnostics and practice of psychological intervention. The authors demonstrated psychopathological mechanisms related to SAD origin and development shows the effectiveness of psycho-pathological approach to diagnostics and therapy. Analyzing the psychopathological approach, the authors revealed that the key mechanisms, which cause SAD, are specific disturbances of target regulation of mental activity and mediation of anxiety during evaluation, changes in the "motive-goal-means" system, social behavior aberrations and distortion of selectivity in mental activity. The comparative analysis revealed that maximum diagnostic and therapeutic efficacy is achieved during combined application of the models in the psychological practice.

A new MHD solver based on the Nektar++ spectral/hp element framework is presented in the paper. A velocity and electric potential quasi-static MHD model is used. The Hartmann flow in a plane duct and its stability, the Hartmann flow in a rectangular duct, and the stability of Hunt's flow are studied as examples. Exponential convergence is achieved and resulting numerical values have been found to have an accuracy up to 10-12 for state flows compared to an exact solution, and to 10-5 for stability eigenvalues compared to independent numerical results. [ABSTRACT FROM AUTHOR]