Enhanced Magnetorheological Performance of Carbonyl Iron Suspension Added With Barium Ferrite Nanoparticle

Hyo Seon Jang,Hyoung Jin Choi,Qi Lu

doi:10.3389/fmats.2021.667685

Abstract

Hard-magnetic barium ferrite (BF) nanoparticles with a hexagonal plate-like structure were used as an additive to a carbonyl iron (CI) microparticle-based magnetorheological (MR) fluid. The morphology of the pristine CI and CI/BF mixture particles was examined by scanning electron microscopy. The saturation magnetization and coercivity values of each particle were measured in the powder state by vibrating sample magnetometry. The MR characteristics of the CI/BF MR fluid measured using a rotation rheometer under a range of magnetic field strengths were compared with those of the CI-based MR fluid. The flow behavior of both MR fluids was fitted using a Herschel–Bulkley model, and their stress relaxation phenomenon was examined using the Schwarzl equation. The MR fluid with the BF additive showed higher dynamic and elastic yield stresses than the MR fluid without the BF additive as the magnetic field strength increased. Furthermore, the BF nanoparticles embedded in the space between the CI microparticles improved the dispersion stability and the MR performance of the MR fluid.

Highlights

Magnetorheological (MR) fluids consisting of soft-magnetic particles suspended in a medium liquid, including silicone oil and mineral oil, are field-responsive functional materials that can be finely controlled from the liquid-like state to a solid-like phase under an applied magnetic field strength (H) (Svåsand et al, 2009; Sedlacík et al, 2010; Susan-Resiga et al, 2010; Qiao et al, 2012; Ashtiani et al, 2015)
This study examined the sedimentation stability and MR performance of MR suspensions by adding nano-sized barium ferrite (BF) particles as an additive between micron-sized carbonyl iron (CI) particles
Hexagonal plate-like BaFe12O19 particles were attached to the space between pure CI particles

Summary

INTRODUCTION

Magnetorheological (MR) fluids consisting of soft-magnetic particles suspended in a medium liquid, including silicone oil and mineral oil, are field-responsive functional materials that can be finely controlled from the liquid-like state to a solid-like phase under an applied magnetic field strength (H) (Svåsand et al, 2009; Sedlacík et al, 2010; Susan-Resiga et al, 2010; Qiao et al, 2012; Ashtiani et al, 2015). Non-circular hexagonal plate-like particles have a slower sedimentation rate than spherical or rod-like particles, such as γ-Fe2O3 and CrO2 These hard magnetic particles that have a special shape could increase the Ms value of the CI particles, which is related directly to improving the MR efficiency of MR suspensions. CIbased MR fluids were fabricated using silicone oil, and the BF additive was added to examine the effect of the additive Their MR behaviors were measured using a rotation rheometer, and the sedimentation stability was recorded using a Turbiscan (MA2000, Formulaction, Toulouse, France). Their MR properties were examined using a rotation rheometer (MCR 302, AntonPaar, Graz, Austria) attached to a device for applying the magnetic field

RESULTS AND DISCUSSION

CONCLUSIONS

DATA AVAILABILITY STATEMENT