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Magnetic Barkhausen noise (MBN) technology is widely used to reveal the microscopic mechanism of magnetomechanical phenomena, but the morphological transition induced by tension has not yet been confirmed by experimental measurements. Here, we report a novel effect on the morphology transition of MBN signals due to tensile stress with pre-introduced strain. We present a power-law relation between the critical stress for the morphology transition and the degree of pre-introduced strain, highlighting the strong correlation between plastic deformation and MBN response. Through comprehensive microscopic simulations, we reveal that dislocations localized in regions with distinct densities trigger different MBN avalanches, thereby leading to a bimodal morphology of the MBN signal. Upon reloading, an effective field introduced by stress promotes the realignment of the magnetic domains, thereby resulting in the formation of a unimodal morphology of the MBN signal. Our unprecedented findings provide valuable insights into the correlation between deformation and MBN signal response, thereby opening a new avenue for designing and optimizing ferromagnetic materials with tailored magnetic behavior. [ABSTRACT FROM AUTHOR]

Seismic damage to components and structures may cause extensive degradation of the seismic capacities of the damaged buildings. The analysis of the residual hysteretic behavior of post-earthquake damaged components and structures is a critical step in the assessment of their residual seismic capacities. Whereas, the difficulty in quantifying the damage distribution of materials in post-earthquake damaged components leads to the challenge of quantitative analysis of their residual behavior (i.e. residual stiffness, strength, energy dissipation). In this study, a visual data-informed fiber beam-column model was developed to analyze the residual hysteretic behavior of post-earthquake damaged RC columns under cyclic loads. To begin with, the method for quantifying the damage strain fields of the columns according to their inspected visual data was proposed. Then, the stress-strain relations of the materials considering the effect of damage strain fields were constructed, and the visual data-informed fiber beam-column model was proposed for the analysis of the residual hysteretic behavior of post-earthquake damaged RC columns subjected to cyclic lateral loads. At last, the proposed model was validated by comparing model results with existing test data. The comparison shows that the proposed visual data-informed fiber beam-column model can accurately analyze the concrete crushing surfaces, the residual load-displacement responses, and the energy dissipation capacities of post-earthquake damaged RC columns, facilitating the evaluation of the residual seismic capacities of post-earthquake damaged RC columns. [ABSTRACT FROM AUTHOR]

The magnetic memory non-destructive testing method can evaluate the early damage such as stress concentration based on the magneto-mechanical effect. Some magneto-mechanical models have been proposed and applied to the mechanism explanation and theoretical analysis of this non-destructive testing method. The present work constitutes a continuing study in questing for a new magneto-mechanical model that is very concise, accurate, and easy to calculate. By introducing a new magnetostrictive expression with a concise and clear physical meaning, a new magneto-mechanical model is proposed under a constant weak magnetic field based on the thermodynamic framework and approach law. Particularly, compared with existing models, an analytical expression of anhysteresis magnetization is obtained for the first time under a constant weak magnetic field, which greatly facilitates the understanding and application of the magneto-mechanical effect. In comparison with the classic Jiles's model, the prediction accuracy is improved greatly based on the present model, particularly for the compression case. A detailed study has also been performed to reveal the effect of cyclic loading on the magneto-mechanical behavior. The present theoretical model established in this paper is hopeful to improve quantitative understanding of magneto-mechanical effects for the magnetic memory method. [ABSTRACT FROM AUTHOR]