Carbonyl Iron Suspension With Core–Shell Structured Fe3O4@SiO2 Nanoparticle Additives and its Magnetorheological Property.

Magnetic Fe3O4@SiO2 nanoparticles were initially synthesized by a sol-gel process and introduced to a soft magnetic carbonyl iron particle-based magnetorheological (MR) fluid to improve its MR properties and dispersion stability. Structure and properties of the core–shell Fe3O4@SiO2 nanoparticles were characterized, showing that they are soft magnetic. MR characteristics of two MR fluid systems with and without Fe3O4@SiO2 additives were investigated and compared under different magnetic field strengths using a rotational rheometer, exhibiting typical MR behaviors. Dispersion stability of the MR fluid was also characterized by an optical analyzer system of Turbiscan. [ABSTRACT FROM AUTHOR]