Effect of Particles Size on the Properties of Nano Core-shell Ni/TiO2 EMR Fluid

By means of mechanical properties test, the relationship among particle size, electric field, magnetic field, electromagnetic field and shear ratio on the Ni/TiO2/Urea core-shell particles electrorheological fluid properties analyses. It is found that with increasing particle size, the property of electrorheological fluid decreased, and with increasing shear ratio the property of electrorheological fluid increased for same composition ER. At same time, the smaller of particle size, the higher of ER properties, but there is a critical value for shear ratio, the properties of ER is near value for same composition ER fluid. In magnetic field, the properties of ER showed a contrary result, the smaller of particle size, the lower of ER properties, and electromagnetic field make the properties increase. Electrorheological fluid is kind of suspension generally made by polarizable particles scatter into liquid. When electric field was exerted, the viscosity, the shear strength of electrorheological fluid instantaneous change, When the electric field was removed, it also can be back to liquid in milliseconds time, a reversible control mechanical behavior makes it have wide application in damper field([1.2]). However, the properties of ER depend on many factors, particle size is one of the most principal factor ([3.4.5]). This paper focuses on the research of properties of Ni/TiO2 electrorheological fluid with different particle size under different electric field, magnetic field and electromagnetic field, analyses the law of properties and subsiding stabilization