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In this article, we studied the phenomenon of instability which is the buckling of the beam elaborated of steel (E36-S355), and magnetorheological elastomer subject to compressionflexion solicitation. The study of the influence of the intensity of the magnetic field on the buckling instability of compressed hybrid beams is done by a mathematical development using the Ritz approach and by a numerical simulation under the Abaqus calculation code. The obtained results show clearly that we can control the instabilities of the adaptive intelligent beams behavior by the magnetic field. Composite hybrid beamRitz approach modeling Numerical simulation Buckling stability

This work presents an analysis experimental of dynamic properties of microcomposite magnetorheological elastomer (MMRE) by a dynamic mechanical analyzer (DMA). The charge of magnetized iron particles is 30% of the total volume. A dynamic mechanical analysis DMA was carried out, in the scanning mode of the amplitude of shear strain, and for magnetic field densities varying from 0mT to 325mT. The storage modulus G' and the loss modulus G'', of the elastomer decrease, when the amplitude of the strain increases. This trend is more pronounced under a higher magnetic flux density (250mT and 325mT). In the presence of the magnetic field, the level of these two dynamic moduli and of the damping increases considerably, passing from one value to another of the applied external magnetic field. As a result, the MR effect of MRE elastomers has increased significantly with increasing magnetic flux density.

The use of magnetorheological elastomers in the mechanical and acoustic fields, by the automotive, aeronautical, and building industries, is currently developing strongly and rapidly. The perfect understanding of the capacity of smart insulation based on the absorption of the vibratory waves by magnetorheological elastomers materials passes by the knowledge of their dynamic mechanical behavior. In this present work, we have characterized the dynamic mechanical properties of the magnetorheological elastomer off axes anisotropy by the inclination, of different angles (15°, 30°, and 45°), of the pseudo-fibers of the iron particles formed by the application of a magnetic field at different intensities using an optimal loading rate of 30%. The rubber specimens were prepared by mixing micron-sized iron particles dispersed in room temperature vulcanized (RTV) silicone rubber by solution mixing. The experimental results obtained show a clear dependence of the effect of inclusion of ferromagnetic chains on the magnetomechanical properties. It is observed that the mechanical properties are better when applying a magnetic field of 0.6 T with an angle of inclination of 45°. The improvements added in this work could be useful in several industrial applications, such as automotive, aeronautic through adaptive control of damping and vibration level.