Parameters of the envelope of the magnetoelastic acoustic emission signal are proposed to be used as informative ones. To study the properties of the envelope of the signal, experimental studies on steel St.3 and nickel specimens are investigated. The signal envelopes for a number of values of the amplitude of the remagnetizing field induction are estimated by several impleŽmentations. It is shown that the shape and duration of the envelope of the magnetoelastic acoustic emission signal depends on the amplitude of the remagnetization field induction, which requires ensuring their stability when using the parameters of the envelope as informative by diagnosing ferromagnetic objects. To test the new informative parameter, uniaxial tensile forces were applied to nickel and steel specimens of the same size and shape (for nickel the stresses were changed from 0 to 110 MPa, for steel to 280 MPa), the specimens were remagnetized with the outside field and the magnetoelastic acoustic emission signals were registered. Estimates signals of the envelope for different values of the applied load are found. The dependences of duration of the magnetoelastic acoustic emission signals on the magnitude of the applied stresses, which can be used as calibration curves for diagnosing residual stresses in ferromagnetic objects of long-term operation, are constructed.

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