Electrorheological properties of Ni-group Nano Particles and Multilayer Compound Polar Molecule Modify

摘要

This paper emphasis has researched the ER properties of Ni group core-shell nano particles modifier with Urea, SDBS and other polar molecule, analysis the relationship among ER properties and polar molecule type , compound modifier under different electric field or magnetic field. It is found that the shear stress increasing with adding polar molecule, compound polar molecule modify can marked advance the properties of Ni group core-shell particles ER fluid. Electrorheological fluid is kind of suspension that polar particles scatter in the oil liquid. When electric field was exerted, the viscosity and the shear strength of electrorheological fluid instantaneous change, the low viscosity fluid flow easily become difficult flow fluid or high viscosity solid. 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 good in transportation, hydraulic equipment and machinery manufacturing, constructional engineering, sensor technology field [1'2]. Modify is one of most important of many factors affecting the ER property. It has proved that polar molecule can greatly increase ER properties. Especially for metal particles, it must be surround by dielectric materials making compound. For Ni particles, it covered with TiO_2, formed Ni/TiO_2 core-shell particles, after that modify by Urea, SDBS etc, sometimes single polar molecule can not satisfied with all the side requirement, compound modifier is a good method in increasing the ER properties. This paper focuses on the research of morphology of particles structure and properties of electrorheological fluid under different electric field, magnetic field and electromagnetic field.