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Magnetoelastic demagnetization of steels 60G and 65G after quenching and tempering under static and dynamic mechanical stress has been studied. According to the results of the research, the magnetoelastic sensitivity to applied loads and its dependence on the steel heat treatment mode were determined. Magnetostriction and coercive force of steels 60G and 65G were measured. The connection of the magnetoelastic sensitivity of the studied steels and the level of elastic stresses with their coercive force and magnetostriction is established. A method for estimating the magnetostriction of structural steel by the magnitude of the coercive force and the level of magnetoelastic demagnetization under mechanical action on steel is proposed. The results obtained can contribute to improving the accuracy of evaluating the elastic stress in a steel structure by magnetoelastic methods. [ABSTRACT FROM AUTHOR]

The remanence of a ferromagnet is formed under the influence of many factors, the main of which are a magnetic field (DC and AC), temperature, mechanical stress, and chemical transformations. Remanences obtained by different ways are differently resistant to external influences. Remanence observed in structural elements may result from one factor or from all of the above. It is shown that the use of remanence as a parameter for assessing the stress-strain state, i. e. the 'method of magnetic memory', without taking into account the conditions of the formation of the remanence state in a product area under testing will have low assessment reliability. [ABSTRACT FROM AUTHOR]

The process of recording ultrasound excited by short laser pulses in metal plates using a wideband EMA receiver was experimentally studied. The investigation results can be used for creating noncontact methods and facilities for ultrasound inspection of thin-sheet metalwares. [ABSTRACT FROM AUTHOR]

As a result of numerical calculations, the spatial and time distributions of the induction of a quasi-stationary magnetic field, which was created in a studied ferromagnet by U-shaped and solenoidal attachable electromagnets (AEMs) at frequencies of 1 and 10 Hz, were obtained. The presence of a phase shift between the amplitude values of the magnetic-field induction at different depths in the specimen, which increases with the frequency of the exciting current, was revealed. The dependences of the magnetic-field penetration depth into the ferromagnet on the magnetic reversal frequency were studied. It was found that for the frequency range under study the magnetic-field penetration depth for both types of AEM is smaller than that for the corresponding stationary case. [ABSTRACT FROM AUTHOR]