Abstract
This work analyses the shear behavior of magnetorheological elastomers (MRE), a class of smart materials which presents interesting magneto-mechanical properties. In order to determine the effect of several variables at a time, a design of experiment approach is adopted. A set of several samples of MRE was manufactured, by varying the weight fraction of ferromagnetic material inside the viscoelastic matrix and the isotropicity of the material, by adding an external magnetic field while the elastomeric matrix was still liquid. The mechanical behavior of each sample was analyzed by conducting cyclic tests at several shear rates, both with and without an external magnetic field. Moreover, in order to estimate the maximum shear stress, the specimens were loaded monotonically up to failure. Shear stiffness, maximum shear stress and specific dissipated energy were calculated on the basis of the experimental data. The results were analyzed using an Analysis of Variance (ANOVA) to assess the statistical influence of each variable. The experimental results highlighted a strong correlation between the weight fraction of ferromagnetic material in each sample and its mechanical behavior. Moreover, the dissipated energy of the MRE drops down when the magnetic field stiffens the behavior or the shear rate increases. The ultimate failure shear stress is strongly affected by the external magnetic field, increasing it by nearly 50%. The ANOVA on the results provides a simple phenomenological model is built for each output variable and it is compared with the experimental tests. These models produce a fast and fairly accurate prediction of each analyzed response of the MRE under various shear rates and applied magnetic fields.
Highlights
The study of magnetorheological elastomers, smart materials whose properties are currently under-utilized for vibration suppression, could lead to a better understanding of the complex interactions between the several concurrent phenomena acting in the material, such as the viscoelastic behavior, the magnetic field dependence and the anisotropicity
The magnetorheological elastomers (MREs), which consist of ferromagnetic micrometric particles suspended in a non-magnetic elastomeric matrix (Davis, 1999; Guan et al, 2008; Ruddy et al, 2008) behave quite opposite to Silly Putty, in that they do exhibit solid-like behavior, even though their response is affected by the load rate
Several works in technical literature (Li, 2013; Popp et al, 2009) are devoted to assess the MREs properties, especially as a function of the shear rate, focusing mainly on cyclic tests but scarce information is provided about their behavior up to failure, the aim of this paper is to provide further information about the shear properties of MREs up to failure, since this important feature helps in the MREs based devices design
Summary
The study of magnetorheological elastomers, smart materials whose properties are currently under-utilized for vibration suppression, could lead to a better understanding of the complex interactions between the several concurrent phenomena acting in the material, such as the viscoelastic behavior, the magnetic field dependence and the anisotropicity. Their use in practical application is still limited to some recent applications such as an automotive MRE mount (Kim et al, 2018), seismic applications (Eem et al, 2019) or a collection of potential applications as proposed in (Li and Zhang, 2012). The aim of this work is to expand the applicability of MREs in engineering application like the more widespread magneto-responsive material: the magnetorheological fluids (MRFs) which exploit the same principle using a fluid matrix and are already used in many industrial applications, especially for vibration damping and shock absorbers (Carlson and Jolly, 2000; Chen et al, 2007; Shen et al, 2004; Spaggiari et al, 2016; Yang et al, 2015)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Intelligent Material Systems and Structures
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
