chandra shekhar maurya
@iitp.ac.in
Scopus Publications
Scopus Publications
Subrat Kumar Behera, Deepak Kumar, Chandra Shekhar Maurya, and Somnath Sarangi
Elsevier BV
Chandra Shekhar Maurya and Chiranjit Sarkar
Elsevier BV
Chandra Shekhar Maurya and Chiranjit Sarkar
SAGE Publications
This study investigates dynamic mechanical properties and creep and recovery behaviors of disc-shaped magnetic Fe3O4 nanoparticles with carbonyl iron (CI) flake-shaped microparticles in water-based MR fluid. The experimental study is performed using a parallel plate rheometer. Dynamic performance and creep and recovery behaviors help understand deformation mechanism for its practical applications in MR devices like seismic vibration control, active dampers, earthquake dampers, etc., under applied strain, and stress levels. The oscillatory experiment reveals a transition from viscoelastic-to-viscous behavior at the critical strain of 0.1%. The storage modulus [Formula: see text] of CI/Fe3O4 MR fluid showed a stable plateau region over the small strain area and storage modulus [Formula: see text] independent of strain amplitude. The frequency experiment demonstrated that storage moduli [Formula: see text] exhibit elastic response and stable plateau region over the complete external frequency range, suggesting the distinguished solid-like behavior of the MR fluid. Creep and recovery experiments showed that fluid acts as a linear viscoelastic material at lower stress levels. As the stress levels increase, the contribution of retardation strain and viscous strain decreases, and it acts like nonlinear viscoelastic material. In summary, this work is expected to obtain MR fluid results for application in MR devices under applied strain, frequencies, and constant stress levels.
Chandra Shekhar Maurya and Chiranjit Sarkar
Springer Science and Business Media LLC
Chandra Shekhar Maurya and Chiranjit Sarkar
Trans Tech Publications, Ltd.
The viscoelastic and creep and recovery behaviors of a carbonyl iron (CI)-water-based magnetorheological fluid (MRF) were studied under dynamic and constant loading conditions. The feature of MR fluid is to change from liquid to semi-solid state just in a few milliseconds after applying a magnetic field. ThereforeMR fluid is a kind of smart material whose rheological properties change with step-change in a magnetic field. We prepared MR fluids comprising CI 65 wt%, water 35 wt %, bentonite 3 wt %, and oleic acid 1 wt %. Because bentonite with nanosized fills the voids between the CI particles, it was used with oleic acid to enhance the MR response of the CI/water suspension. The strain amplitude tests reveal that MR fluid behaves as a viscoelastic material in the LVE range and a transition of fluid occurred from linear viscoelastic to non-linear viscoelastic behavior at the critical strain of 0.1%. Its storage moduli confirmed a steady plateau region for the entire angular frequency range, suggesting the well-known solid-like behavior of the MR suspension. The creep and recovery result signified that as the magnetic field increased, the instantaneous creep strain contributions decreased dramatically.
Chandra Shekhar Maurya and Chiranjit Sarkar
SAGE Publications
In this study, micron-sized flake shaped carbonyl iron (CI) water-based MR fluids were prepared with adding laponite and oleic acid as an additive and surfactant, respectively. The MR suspensions are comprised of the fixed CI particles and water weight %, while weight % of laponite and oleic acid changes from 1 to 3 wt% and 0.5 to 1.5 wt%, respectively. The remarkable enhancement in magnetorheological properties was obtained with improved sedimentation stability for CI/water MR suspensions with the addition of laponite and oleic acid. It was found that at the lowest magnetic field strength, the higher laponite concentration is effective, while at the highest magnetic field strength, the smaller concentration was effective. It was because of the combined effect of the field-induced CI chains and the laponite clay gel network. Its storage moduli showed a stable plateau area for whole angular frequencies, suggesting distinguished solid-like behavior of the MR fluid. Finally, a novel correlation was obtained between the initial settling rate of the CI particles and magnetorheological behavior of CI/laponite/OA MR suspensions with 1 wt% laponite and 0.5 wt% oleic acid, which has less zero-field, high on-state shear stress with enhanced sedimentation stability. The prepared MR fluids are a reliable industrial application vibration-isolation, clutch, and brake.
Chandra Shekhar Maurya and Chiranjit Sarkar
Springer Science and Business Media LLC
Chandra Shekhar Maurya and Chiranjit Sarkar
Institute of Electrical and Electronics Engineers (IEEE)
To analyze the effect of magnetite Fe3O4 disk-shaped nanoparticles with flake-shaped microparticles in water-based magneto rheological (MR) suspension, the rheological properties were studied using a parallel plate rheometer. The morphology, crystallinity, and magnetic property of the prepared MR suspensions were examined by field emission scanning electron microscopy (FESEM), X-ray diffraction, and vibrating sample magnetometer, respectively. In the presence of a magnetic field, micron-sized carbonyl iron (CI) particles lead to form a robust columnar structure with Fe3O4 nanoparticles and enhanced the magnetorheological performances. The magnetorheological performances of MR suspensions were examined in shear rate, shear strain, and shear stress testing sweep modes with and without a magnetic field. It was observed that adding the 1 wt% of Fe3O4, the magnetorheological performance of MR suspension enhanced. The MR fluid with CI/Fe3O4 nanoparticle mixture showed significantly higher shear viscosity and shear stress and yielded stresses than pure CI-based MR fluid. The yield stresses were higher in the shear rate sweep mode than strain and stress sweep testing modes.
Chandra Shekhar Maurya and Chiranjit Sarkar
Institute of Electrical and Electronics Engineers (IEEE)
This article presents a numerical simulation of a plate–plate magnetorheometer using the finite-element method. In this design of the rheometer, the electromagnetic coil generates a high and a constant magnetic-flux density (1.1 T at 3 A coil current) along the radius of the magnetorheological (MR) region. A uniform magnetic-flux density is distributed over the area of the MR region due to which there are no effects of magnetic-flux gradients on the MR properties. The other benefit of the proposed design is the reduction of electromagnetic heating effects on the MR sample. A uniform temperature generated in the MR region is 299 K due to the electromagnetic coil at 3 A current and 1.1 T magnetic-flux density after 30 min, while the maximum temperature caused due to electromagnetic coil heating is about 337 K around the coil. The temperature generated due to the slippage of MR fluid is 306 K at the same operating conditions. Thus, this design of the magnetorheometer minimizes the total temperature generated due to the electromagnetic coil and slippage in the MR region. Finite–element simulation involves magnetostatic, laminar fluid flow, and heat transfer analysis.