Microstructural characterization and effective viscoelastic behavior of magnetorheological elastomers with varying acetone contents

Abstract

Magnetorheological elastomers (MREs), a class of polymer-based composites with dispersed ferromagnetic micro-particles, fall in the class of smart materials, because their macroscopic or effective rheological properties can be continuously, rapidly, and reversibly changed with the application of a magnetic field. Conventional magnetorheological elastomers exhibit poor mechanical properties and magnetorheological effect as a result of their matrix materials and the particle-matrix interfaces. Here, we investigate the effect of acetone contents on the magnetorheological elastomer microstructure at the interfacial regions using the scanning electron microscope and the three-dimensional nano-CT imaging, as well as determining the overall or effective mechanical properties of magnetorheological elastomers. It is shown that acetone increases both the overall storage modulus and loss factor along with the magnetorheological effect due to acetone’s reaction on the interface as well as its effect on iron particle alignment.

A Review of Magnetic Elastomers and Their Role in Soft Robotics

“…These properties of MEs, specifically their microstructure, have been confirmed through various methods, such as scanning electron microscopy, which can show the isotropic or anisotropic arrangement (Gong et al, 2005;Nayak et al, 2015;Jung et al, 2016;Damiani and Sun, 2017). Energy-dispersive X-ray spectroscopy (Nayak et al, 2015;Jung et al, 2016) and threedimensional nano-computed tomography imaging have also been used to validate the alignment of the magnetic particles within the matrix (Damiani and Sun, 2017).…”

Micro-CT-based micromechanics and numerical homogenization for effective elastic property of ultra-high performance concrete

“…In their studies, CT was applied to investigate the connectivity and tortuosity of the pore network in cement pastes, which are significant parameters to evaluate the overall mechanical properties and the durability of cement mortars. In addition, X-ray CT has been also applied to characterize microstructural damage of other heterogeneous materials (Chen et al, 2017;Damiani and Sun, 2017;Shen et al, 2013;Suchorzewski et al, 2018). Furthermore, this technique has been utilized to characterize the microstructure and mechanical properties of FRC, such as the orientations of fiber or aggregates (Bordelon and Roesler, 2014;Wong and Chau, 2005) and measurement of fracture energy (Yu et al, 2015).…”

A micromechanics-based elastoplastic constitutive model for frozen sands based on homogenization theory

“…However, for frozen soils, few attempts were made to consider the microstructures by means of continuum micromechanics and homogenization theory of heterogeneous materials. During the last decades, many researchers have made investigations on unfrozen reinforced composite materials, mainly focusing on the interactions between the matrix and inclusions in micro-scale perspective to simulate the macroscopic stress–strain responses (Ayadi et al., 2018; Chen et al., 2017; Damiani and Sun, 2017; Diamantopoulou et al., 2017; Egner and Ryś, 2017; Ganjiani, 2018; Hassanifard and Feyzi, 2017; Jin and Arson, 2018; Mizuno, 2017; Park et al., 2017; Pupurs and Varna, 2017; Wu and Ju, 2017; Zhang et al., 2017). Sun et al.…”