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The article presents the results of a study of the effect of mechanical load on the temperature dependence of the initial permeability of LiTiZn soft ferrite ceramics. Regimes of mechanical load were created by a steel non-magnetic ring with screws. In this work, four levels of mechanical load were investigated: without load, with 1, 2 and 3 screws. For obtaining temperature dependences and exclude the influence of prehistory on the initial permeability, the samples were heated to a temperature exceeding the Curie point by 50 degrees, after which they slowly cooled to room temperature. The defects level was determined by the ratio of the parameters β / α of the phenomenological expression, which describes the experimental temperature dependences. It is shown that as the mechanical load increases, the defects level of ferrite ceramics increases, and after load removing, it returns to its original level.

The paper addresses the diagnosis of the presence of defects in concrete, cement-sand and other building and structure mixes using mechanoelectrical transformations. The problem of high levels of electromagnetic noise and interference affecting the correct interpretation of the data to diagnose presence of defects is considered. A version of the electromagnetic response from the unit heterogeneity is proposed, and the assumption of the total electromagnetic signal is suggested. The experiment on acoustic excitation of the sample was conducted and the electromagnetic responses were recorded and filtered using the correlation analysis. The obtained result was compared to the model one to confirm the single response model.