Dynamic simulation studies of structural formation and transition in electro-magneto-rheological fluids

The computer simulation method has been used to study the structural format ion and transition of electro-magneto-rheological (EMR) fluids under compat ible electric and magnetic fields. When the fields are applied simultaneous ly and perpendicularly to each other, the particles rapidly arrange into tw o-dimensional close-packed layer structures parallel to both fields. The la yers then combine together to form thicker sheet-like structures, which fin ally relax into three-dimensional close-packed structures with the help of the thermal fluctuations. On the other hand, if the electric field is appli ed firstly to induce the body-centered tetragonal (BCT) columns in the syst em, and then the magnetic field is applied in the perpendicular direction. the BCT to face-centered cubic (FCC) structure transition is observed in ve ry short time. Following that. the structure keeps on evolving due to the d emagnetization effect and finally form the three-dimensional close-packed s tructures.