Magnetorheological Elastomers Samples Research Articles

Development of MRE-based metamaterial with adjustable frequency bandgap for seismic vibration isolation

A seismic isolation system is an engineering method to prevent structures from the undesirable vibrations of earthquake. It involves using isolators, dampers, and bearings to decouple the superstructure from the ground during seismic waves by reducing the forces and accelerations transferred to the structure. The goal of this research is to investigate the tunable MRE-based metamaterial foundation for seismic vibration isolation. Metamaterials with adaptive and variable frequency band gaps are preferred because earthquakes have a wide range of frequencies. By varying the magnetic field intensity, a magnetorheological elastomer (MRE)-based metamaterial foundation can modify its Young's modulus and stiffness. The frequency band gap or frequency range of the MRE-based metamaterial foundation can be shifted by tunable material properties. Under the effect of a magnetic field, a uniaxial compression test was conducted to evaluate the Young's modulus of three types of MRE samples. Following the compression test, a series of numerical simulations in ABAQUS were carried out using a two-story framed building with RC and MRE-based metamaterial foundation. Three earthquake excitations are used: Bishop, Oroville, and Imperial Valley. The experimental results suggest that the magnetic field influences the MRE's Young's modulus. Similarly, numerical simulation studies indicate that the magnetic field influences the frequency band gap of the MRE-based metamaterial foundation. The FRF results of conventional RC foundation and MRE-based foundation are compared, highlighting the efficiency of MRE-based foundation in vibration control by reducing the seismic vibration of a structure by 68.5 %.

Morphological features of magnetorheological elastomer degradation under a natural weathering environment

It is well known in the field of materials science that a substance’s longevity is significantly influenced by its environment. Everything begins with the initial contact on a material’s surface. This influence will then deteriorate and have an extended negative impact on the strength of the material. In this study, the effect of natural weathering in tropical climates on magnetorheological elastomer (MRE) was investigated through microstructural evaluation to understand the aging behavior of the environmentally exposed MRE. To understand and elucidate the process, MREs made of silicone rubber and 70 wt% micron-sized carbonyl iron particles were prepared and exposed to the natural weathering of a tropical climate for 90 days. The MRE samples were then mechanically tensile tested, which revealed that Young’s modulus increased, while elongation at break decreased. Surface degradation due to weathering was suspected to be the primary cause of this condition. Using scanning electron microscopy (SEM), the degradation of MRE was investigated as a function of morphological evidence. Upon examination through SEM, it was noted that the weathering effects on the morphology of the exposed samples showed distinct characteristics on the degraded surfaces of the MRE, including numerous microvoids, cavities, and microcracks. While these features were not prominent for the MRE itself, they bear resemblance to the effects observed in similar materials like rubber and elastomer. An atomic force microscope (AFM) is used to investigate the surface topography and local degradation conditions. This observation revealed a distinctive degradation characteristic of the MRE in connection to natural weathering in tropical climates. The surface damage of the MRE samples became severe and inhomogeneous during the environmental aging process, and degradation began from the exposed MRE surface, causing the mechanical characteristics of the MRE to significantly change.

Developing adjustable stiffness for smart material of magnetorheological elastomer to diminish vibration

Many vibration isolators, such as passive vehicle mounting devices, have an inflexible stiffness. This article presents the development of a smart material vibration isolator based on magnetorheological elastomer (MRE), which has adjustable stiffness to minimize unwanted vibrations. The objective of this research is to first create a design for the vibration isolator, and then simulate a magnetic circuit. The Finite Element Method Magnetics (FEMM) software was employed to simulate the effectiveness of the electromagnetic circuit in generating a magnetic field through the vibration isolator by employing MRE samples. Pure iron was chosen as the material for the housing of the vibration isolator test rig. To attain an optimal magnetic field, an inventive design of the magnetic circuit, including examination of the wire type, size, and coil turn number, along with the housing material of the test rig, was performed. The study analyzed the performance of the MRE vibration isolator concerning different current inputs in the coil. The results indicate that the stiffness value of the MRE-based isolator system can be more effectively modified by increasing the current inputs. Therefore, a larger current input leads to a greater change in stiffness.

Magnetorheological effect and sensing performance of graphite sheet filled PDMS based magnetorheological elastomer under compression

In order to study the effect of large-sized graphite (Gr) sheet on the magnetorheological (MR) effect and sensing characteristics of MR elastomer (MRE), isotropic and anisotropic Gr-filled MRE samples with different carbonyl iron powder (CIP) contents were fabricated. The effect of Gr sheet on the microstructure, MR effect and sensing characteristics of the MRE samples were experimentally tested, and the mechanisms behind discussed. The results show that in the anisotropic MRE samples, the addition of Gr sheets results in the short particle chains formed between Gr sheets, thus leading to the high MR effect and low resistivity than those of isotropic counterparts. The non-monotonic resistivity responses of the Gr-filled MRE samples during compression were observed owing to the interlayer separation of Gr sheets and the reconstruction of conductive network. A higher piezoresistive response was observed from the isotropic Gr-filled MRE sample filled with the CIP content below the percolation threshold. The resistivities of the Gr-filled MRE samples decline with increasing the applied magnetic field. The isotropic sample filled with lower CIP content shows the higher magnetoresistive effect from the view point of absolute change in resistivity. While for the relative change in resistivity, the anisotropic sample filled with the higher CIP content has the higher magnetoresistive effect.

Development of a Novel Magneto-Rheological Elastomer-Based Semi-Active Seat Suspension System

Human operators in the transportation sector are exposed to whole-body vibration (WBV) while driving. Occupational exposure to WBV, predominant at low frequencies (<20 Hz), has been linked to spinal injuries and reduced functioning. This study aims at the design development of a novel semi-active seat suspension system featuring magneto-rheological elastomers (MREs) to mitigate the WBV. The proposed suspension system allows a greater range of strokes, while ensuring the MRE remains within an acceptable level of deformation. Several MRE samples were fabricated and characterized under shear mode. Afterward, a field- and frequency-dependent phenomenological model was developed to predict the viscoelastic properties of MREs as functions of both the excitation frequency and applied magnetic field. The MRE material model was subsequently used to design and optimize an adaptive seat suspension system incorporating a C-shaped MRE-based isolator in parallel and series with passive springs. The proposed adaptive seat suspension system demonstrated a frequency shift of 29% by increasing the applied current from 0 to 2 A. Finally, a 6-DOF lumped parameter model of a seated human subject combined with the proposed semi-active suspension system featuring the MRE isolator has been formulated to investigate the vibration transmissibility from the floor to the subject’s head.

Perceptibility of programmable softness displays using magnetorheological elastomers

While often focused on our visual system, adding touch to VR/AR environments can help render more immersive, richer user experiences. One important touch percept to render is compliance, or ‘softness.’ Herein, we evaluate the perceptibility of soft, magnetorheological elastomers (MRE) in bare-finger interactions. Such materials can be reprogrammed to distinct states of compliance. We fabricated MRE samples over elastic moduli from 23–173 kPa and measured that small 0.25 T magnetic fields increased modulus by 10–60 kPa. MRE interfaces less and more compliant than finger skin were evaluated in discrimination experiments with and without a magnetic field. The results indicate changes in modulus of 11 kPa are required to reach a 75% threshold of discrimination, although greater differences are required when an MRE’s elasticity is about the same as skin. The perceptual results with these magnetically-induced materials are similar to those with non-actuated, solid silicone-elastomers that mimic naturalistic interactions.

An experimental investigation on the matrix dependent rheological properties of MRE

The rheological properties of magnetorheological elastomers are influenced by magnetically sensitive fillers and the elastomer matrix. The ability to respond to an external magnetic field is imparted by the fillers, while the load-bearing capability is determined by the matrix type. In this paper, the effect of matrix material on the properties of magnetorhological elastomer is explored experimentally. Carbonyl iron particle content is varied by 0%, 15% and 25% by volume to produce magnetorheological elastomer samples using natural rubber, silicone rubber and nitrile butadiene rubber matrices. Forced transmissibility test approach was employed to evaluate the field induced variations in the dynamic stiffness and loss factor of magnetorheological elastomers. The dynamic stiffness of nitrile butadiene rubber is the highest, while that of silicone rubber is the lowest. Addition of carbonyl iron particles significantly improves stiffness, although these gains depend on the properties of unfilled matrix. The addition of 25% by volume of carbonyl iron particle increased the dynamic stiffness of a silicone rubber matrix based magnetorheological elastomer by 67.78%, while the similar change in magnetorheological elastomer with nitrile butadiene rubber matrix was 38.58%. The field dependent response of magnetorheological elastomers is governed by the matrix and ferromagnetic filler concentration. These qualities are higher in magnetorheological elastomer with a low initial dynamic stiffness matrix and lower in magnetorheological elastomers with a stiffer matrix.

Particle-reinforced elastomer model to analyse viscoelastic properties of flake-shaped electrolyte iron particle-based magnetorheological elastomer

This paper uses parallel-plate-plate rheometry to focus on the magnetic field-dependent nonlinear viscoelastic behaviour of flake-shaped electrolyte iron powder-based magnetorheological elastomer (MRE). MRE was prepared using liquid silicon rubber as a base, a curing agent and electrolyte iron particles as fillers. Three MRE samples having 60%, 40%, and 0% filler weight fractions were prepared. The curing was carried out at 300 K. The thickness of the sample was 1.00 ± 0.04 mm. Scanning electron microscopy results showed uniform dispersal of particles within a matrix. The swelling measurement technique was used to confirm the enhanced reinforced properties of elastomer by calculating the cross-link density. The magnetic volume fraction evaluated from magnetisation measurements yields values of 18.7% for MRE-60 and 8.7% for MRE-40. Both moduli’s field-induced linear and nonlinear amplitude dependence were analysed using the modified particle-reinforced elastomer model. The result indicates that filler particles adsorbed on polymer chains were essential in determining the reinforcing properties of MRE. The improved cross-link density and particle morphology were responsible for the enhanced field-induced magnetorheological effect (277%). This value is nearly three times greater than that observed in spherical particles-based MRE.

Properties of inhomogeneous-type magnetorheological elastomer formed in the presence of a magnetic field with tilted angles

Magnetorheological elastomers (MRE) are smart materials whose mechanical properties can be tuned using an applied magnetic field. Many studies have shown that MRE properties are influenced by particle size, particle volume fraction, and matrix material type. The particle-magnetic dipole theory has demonstrated that the angle of the particle chains significantly affects the properties. This study investigated the effects of the alignment angle of the particle chains on the properties of MREs. The inclination angle is a parameter associated with the external magnetic flux density. MRE samples fabricated under a magnetic field with different tilt angles were prepared for the shear tests. The primary properties of MRE, such as viscoelasticity, magnetic-induced properties, and hysteresis, were comprehensively investigated in the samples. The equivalent stiffness and loss of energy changed significantly in the tilted angle domain. The force–displacement loops also showed a clear difference among the samples when the experiments were performed at the same amplitude, frequency, and magnetic flux density. The experimental results show that the magnetic and hysteretic properties strongly depend on the initial tilt angle of the chain.

Microstructure modeling and experimental verification of isotropic magnetorheological elastomers based on edge-centered cubic structure

Aiming at the problem that the existing mechanism cannot accurately predict the shear properties of magnetorheological elastomers (MREs), in this research, a physical microscopic constitutive model of isotropic MREs based on an edge-centered cubic (ECC) lattice structure was constructed to accurately reflect the shear properties of isotropic MREs under quasi-static and dynamic shear modes and different magnetic fields. In order to reduce the error of the potential energy model in the modeling process, the accuracy of the MRE total potential energy theoretical model based on the ECC lattice structure was improved by transforming to under finite strain, and the maximum improvement rate of the model accuracy was 6%. Then, in order to construct a microstructure-based dynamic model, the Langevin equation was constructed based on the ECC lattice, and an exact solvable model of the topological regular network was constructed by the Rouse chain. The relationship between the relaxation time, eigenvalue and magnetic flux density was revealed, and then the updated shear modulus was solved. Then, the modulus values of the prepared isotropic MRE samples at different frequencies and magnetic flux densities were compared with the theoretical model values, and the model failure phenomenon under dynamic high magnetic field, in which the theoretical results are inconsistent with the experimental results, was modified by the method of piecewise function and optimization parameters. The final results show that the correlation coefficient between the experimental results and the theoretical results can reach 99%.

Transient dynamics of the field induced force in the isotropic magnetorheological elastomer

The transition dynamics in silicon rubber based isotropic magnetorheological (MR) elastomers in terms of the normal force induced by an external homogeneous magnetic field is experimentally addressed. The primary goal was to evaluate dynamic performances of the MR elastic isotropic composite using a transparently presented measuring system with known characteristics in contrast to few previous studies on the topic. It was found that an increase in the magnetic field leads to an increase in the induced force and a decrease in the response time of the MR elastomer. At the same time, both the use of coarse particles as magnetic filler and a significant reduction in the stiffness of the polymer matrix reduce the response time of the MR elastomer under study. The analysis carried out takes into account the dynamics of the electromagnetic coil and the eddy currents induced in the magnet circuit. The shortest response times obtained for various MR elastomer samples are in the range of 27–72 ms for the maximal used magnetic field with an induction of 230 mT. These times correspond to the fastest previously reported ones for MR elastomers and MR elastomer based systems. In addition, the obtained results indicate the presence of different mechanisms responsible for the measured magnetodeformational effect observed in MR elastomers.

Hysteresis Behavior Modeling of Magnetorheological Elastomers under Impact Loading Using a Multilayer Exponential-Based Preisach Model Enhanced with Particle Swarm Optimization.

Magnetorheological elastomers (MREs) are a type of smart material that can change their mechanical properties in response to external magnetic fields. These unique properties make them ideal for various applications, including vibration control, noise reduction, and shock absorption. This paper presents an approach for modeling the impact behavior of MREs. The proposed model uses a combination of exponential functions arranged in a multi-layer Preisach model to capture the nonlinear behavior of MREs under impact loads. The model is trained using particle swarm optimization (PSO) and validated using experimental data from drop impact tests conducted on MRE samples under various magnetic field strengths. The results demonstrate that the proposed model can accurately predict the impact behavior of MREs, making it a useful tool for designing MRE-based devices that require precise control of their impact response. The model's response closely matches the experimental data with a maximum prediction error of 10% or less. Furthermore, the interpolated model's response is in agreement with the experimental data with a maximum percentage error of less than 8.5%.

The effect of salt water ageing on the mechanical and rheological properties of magnetorheological elastomer

This paper aims to investigate the mechanical and rheological properties of magnetorheological elastomer (MRE) in marine ecosystems. The prepared samples comprised silicone rubber (SR) and 70 wt% micron-sized carbonyl iron particles (CIPs), immersed in an artificial marine ecosystem using salt water (Natrium Chloride) for 30 days. The mechanical properties of MRE samples were evaluated using hardness and quasi-static tensile tests. While the rheometer was used to investigate the rheological properties of their storage modulus condition with magnetic field stimulation. Further analysis of the defects and damages caused by salt water ageing was done through morphological observation using scanning electron microscope (SEM) technology. The results showed that the hardness and tensile strength of MRE samples that were soaked in salt water were affected over time. Lower values of hardness and tensile strength were obtained after 30 days due to the presence of Na+ and Cl−, which acted as an accelerator to the hydrolyzation process of the MRE. The process then, enhanced the water ingress capability into the matrix to cause the molecular changes. Interestingly, for rheological properties, 30 days of salt water ageing allowed the water molecules to move the MRE matrix molecular chains apart, a process known as plasticization and thus increasing the MR effect. Furthermore, morphological evidence was established to determine the MRE changes during salt water ageing. The research findings should greatly contribute to a better understanding of the effect of salt water on the performance of MRE.

Magnetorheological behavior of thermoplastic elastomeric honeycomb structures fabricated by additive manufacturing

3D printing of magnetorheological elastomers (MREs) can potentially create versatile and complex mechanical structures with reversible stiffening properties. Several additive manufacturing (AM) methods, like direct printing and stereolithography (SLA), have been used to achieve magnetic thermoset and elastomer composite structures. For the first time, we demonstrate the use of MREs based on thermoplastic elastomers (TPE) in AM and we investigate their magnetorheological (MR) effect when used in lightweight honeycomb designs. Due to the low shore hardness of TPE, a screw extruder-based printing head is employed to print disk-shaped samples with honeycomb patterns at infill percentages varying from 15% to 50%. In order to compare the MR effect of disks with varying honeycomb infills through a compression method, we investigated the effect of different testing configurations. We observe that different permanent magnet configurations, as it has been used in literature so far, create an additional effect on the measured MR effect of the MRE samples. To eradicate this effect, a test setup with an unpaired permanent magnet configuration is proposed. MRE structures with an infill density of 20% showed, at 1% deformation range, the highest MR effect, almost four times as high as 100% infilled samples. MRE structures with an infill density between 30% and 50% showed a lower MR effect than at 20%, but were still higher than at 100%. We observe in simulations that the magnetic flux density of 100% infilled samples was higher at the edges of the samples and lower at the center. For samples with honeycomb infill, the magnetic flux density was higher at the outer rim of the samples and edges of the walls within the sample, which causes a higher MR effect. Our work demonstrates that the MR effect can be tuned by designing a MRE structure with a honeycomb infill. The honeycomb infill results in lightweight MREs with improved MR effect useful for various downstream applications that require reversible strong stiffening while remaining comparatively lightweight.

Enhancement of Magneto-Induced Modulus by the Combination of Filler and Plasticizer Additives-Based Magnetorheological Elastomer

Filler additive is used to provide superior bonding in rubber matrix to enhance the storage modulus of magnetorheological elastomer (MRE). However, the magneto-induced modulus is reduced as the initial storage modulus increases. Therefore, this paper aims to increase the magneto-induced modulus and maintain the initial storage modulus by combining filler and plasticizer additives. Both types of additives have different functions, where cobalt ferrite (CoFe2O4) is capable of enhancing the maximum storage modulus and silicone oil (SO) reduces the initial storage modulus. Thus, four MRE samples have been fabricated using (a) no additive, (b) CoFe2O4, (c) SO, and (d) a combination of CoFe2O4 and SO. The sample’s hardness and magnetic properties were investigated via Durometer Shore A and Vibrating Sample Magnetometer (VSM), respectively. Furthermore, the rheological properties of MRE samples in terms of storage modulus were investigated upon the frequency and magnetic field sweep using a rheometer. The results demonstrated that the storage modulus of the MRE samples has increased with increasing the oscillation frequency from 0.1 to 50 Hz. Interestingly, the combination of additives has produced the largest value of magneto-induced modulus of 0.90 MPa as compared to other samples. Furthermore, their initial storage modulus was in between samples with SO (lowest) and without additive (highest). Therefore, fundamental knowledge in adding the combination of additives can offer solutions for a wide range of stiffness in MR device applications such as vibration and noise control devices, sensing devices, and actuators.

Influence of Gamma Radiation on the Damping Property of Magnetorheological Elastomer.

Magnetorheological elastomer (MRE) is a kind of smart material, whose mechanical property can be controlled by the external magnetic field quickly and reversibly. The damping property of MRE is one of the most concerned properties when designing MRE based devices. In this work, the influence of gamma radiation on the damping property of MRE was investigated. Six different exposures of gamma radiation were applied to the MRE samples. The highest gamma radiation dose was up to 1 × 105 Gy(Si), which can cover most of the engineering application scenarios. The influence of gamma radiation on the damping-strain relation and the damping-magnetic-field relation were studied. The probable mechanisms were discussed in detail. It is found that the gamma radiation does not affect the variation trend of loss factor of MRE with increasing strain amplitude or magnetic flux density. But it affects the variation trend of the maximum change of strain-induced or magnetic-field-induced loss factor of MRE. Besides, with constant strain and constant magnetic flux density, the loss factor of MRE shows w-shape variation trend with increasing gamma radiation dose. It is considered to be resulted from the combined action of the intrinsic damping and the interfacial friction damping of MRE.

Natural Weathering Effects on the Mechanical, Rheological, and Morphological Properties of Magnetorheological Elastomer (MRE) in Tropical Climate.

Magnetorheological elastomer (MRE) materials have the potential to be used in a wide range of applications that require long-term service in hostile environments. These widespread applications will result in the emergence of MRE-specific durability issues, where durability refers to performance under in-service environmental conditions. In response, the outdoor tropical climatic environment, combined with the effects of weathering, will be the primary focus of this paper, specifically the photodegradation of the MRE. In this study, MRE made of silicone rubber (SR) and 70 wt% micron-sized carbonyl iron particles (CIP) were prepared and subjected to mechanical and rheological testing to evaluate the effects under natural weathering. Magnetorheological elastomer samples were exposed to the natural weathering conditions of a tropical climate in Kuala Lumpur, Malaysia, for 30 days. To obtain a comprehensive view of MRE degradation during natural weathering, mechanical testing, rheology, and morphological evaluation were all performed. The mechanical and rheological properties test results revealed that after 30 days of exposure and known meteorological parameters, Young’s modulus and storage modulus increased, while elongation at break decreased. The degradation processes of MRE during weathering, which are responsible for their undesirable change, were given special attention. With the help of morphological evidence, the relationship between these phenomena and the viscoelastic properties of MRE was comprehensively defined and discussed.

A novel methodology for accurate estimation of magnetic permeability of magnetorheological elastomers

Identifying a reliable nonlinear B-H curve for magneto-rheological elastomers (MREs) is a fundamental necessity for modeling and optimal design of MRE-based devices, particularly in the initial design stages. The main contribution of this study is to propose a novel methodology for the accurate estimation of magnetic permeability and nonlinear B-H curve for MREs. The proposed method involved three series of simple experiments employing an air gap electromagnet, which required only a Gauss meter to measure air gap magnetic flux density, together with formulation of an equivalent magnetic circuit (EMC). The data acquired from the first two series of experiments were used to characterize the relative magnetic permeability of MREs, while that obtained from the third series of experiments permitted an accurate estimation of the nonlinear B-H curve. For this purpose, isotropic MRE samples with 30% particle volume fraction were fabricated. Results showed that the relative magnetic permeability of MREs decreases with increasing magnetic field. The effectiveness of the proposed methodology for estimating magnetic permeability was demonstrated by comparing with that obtained from a VSM device, which revealed relatively low prediction error of 4.1%. The proposed method could thus be utilized for characterization of nonlinear magnetic permeability of MREs with minimal complexity and cost. The proposed methodology, unlike the VSM devices, could predict magnetic properties of MRE under tension/compression loadings.

Effect of Cyclic Shear Fatigue under Magnetic Field on Natural Rubber Composite as Anisotropic Magnetorheological Elastomers.

With the development and wide applicability of rubber materials, it is imperative to determine their performance under various conditions. In this study, the effect of cyclic shear fatigue on natural-rubber-based anisotropic magnetorheological elastomer (MRE) with carbonyl iron particles (CIPs) was investigated under a magnetic field. An anisotropic MRE sample was prepared by moulding under a magnetic field. Cyclic shear fatigue tests were performed using a modified electromechanical fatigue system with an electromagnet. The storage modulus (G′) and loss factor in the absence or presence of a magnetic field were measured using a modified dynamic mechanical analysis system. Under a magnetic field, fatigue exhibited considerable effects to the MRE, such as migration and loss of magnetised CIPs and suppressed increase in stiffness by reducing the energy loss in the strain cycle. Therefore, the G′ of the MRE after fatigue under a magnetic field was lower than that after fatigue in the zero field. The performance of the MRE, such as absolute and relative magnetorheological effects, decreased after subjecting to cyclic shear fatigue. In addition, all measured results exhibited strain-dependent behaviour owing to the Payne effect.

Development of a Performance-Enhanced Hybrid Magnetorheological Elastomer-Fluid for Semi-Active Vibration Isolation: Static and Dynamic Experimental Characterization.

Magnetorheological elastomers (MREs) are a class of emerging smart materials in which their mechanical and rheological properties can be immediately and reversibly altered upon the application of a magnetic field. The change in the MRE properties under the magnetic field is widely known as the magnetorheological (MR) effect. Despite their inherent viscoelastic property-change characteristics, there are disadvantages incorporated with MREs, such as slow response time and the suspension of the magnetic particles in the elastomer matrix, which depress their MR effect. This study investigates the feasibility of a hybrid magnetorheological elastomer-fluid (MRE-F) for longitudinal vibration isolation. The hybrid MRE-F is fabricated by encapsulating MR fluid inside the elastomer matrix. The inclusion of the MR fluid can enhance the MR effect of the elastomer by providing a better response to the magnetic field and, hence, can improve the vibration isolation capabilities. For this purpose, an MRE-based coupling is developed, and isolation performance is investigated in terms of the linear transmissibility factor. The performance of the hybrid MRE-F was compared against two different MRE samples. The results show that further enhancement of MR-effect in MREs is possible by including MR fluid inside the elastomer. The hybrid MRE-F exhibited better stiffness change with the current increase and recorded the highest value of . The transmissivity curves revealed that the MRE-F contributed to a broader shift in the natural frequency with a overall shift at . The damping characteristics are higher in MRE-F, recording the highest percentage increase in damping with . Overall, the results reveal the promising potential of hybrid MRE-F in developing MRE-based coupling for longitudinal vibration isolation.