A Study Of Preparation And Stability Of Magnetorheological Fluid

Magneto-rheological Fluid is a new type intelligent materials, which is composed of dispersed particles, carrier fluid and additive. The MRF is Newtonian fluid without external magnetic filed. The MRF is transferred to solid-state immediately in external magnetic fluid in milliseconds, and changed to be Newtonian fluid immediately while removes the external magnetic. In recent years, it would always be the research focus in scientific community at home and abroad because of its MR effect and controllable in magnetic field, so that it has been greatly applied in many fields. With the developing research on the application of MRF, the stability problems of MRF would seriously affect its prospect of engineering application. The stability problem of MRF has not been solved well, due to the complication of the composition with MRF and application environment.The thorough research to production of MRF and stability of MRF would be made in following articles, according to the preparation technology of MRF and stability. The stability principle of MRF, prepares MRF samples, promotes sedimentation stability, etc would be analyzed in this paper. The main contents were as follows:The basic properties of MRF was introduced in this paper, such as rheology mechanism, application, composition and classification. Meanwhile, the article reviewed the development of preparation technology, and methods which were used to promote the stability, summarized the still existing problems and stability problems which were need to be solved urgently at this stage.The properties of MRF, the agglomeration stability principle and sedimentation stability principle based on gravity field were analyzed. And The magnetic particles,viscosity of based fluid, additive, nano particles and the process of preparation that may affect the stability of MRF would be researched in this article.The composition of MRF were analyzed and selected, the formula were designed, and several samples of MRF were prepared, that was used to promote stability of MRF. Thedefects of traditional preparation process were summarized, thus a kind of ball milling preparation process would be designed in this paper. And then the properties of two samples what were prepared in different preparation process were tested, for instance, the stability and viscosity at zero external magnetic field. Finally the Ball milling process was made a great influence in promoting stability according to comparative analysis.The influencing factors of MRF properties were researched by experiment, such as mass fraction and particle size of magnetic particles, mass fraction of thixotropic agent and surfactant, ball milling time, temperature, etc, that was to prepare the MRF sample with good performance and well stability.The three levels was designed including silane coupling agent KH-560, Nano-SiO2 and graphite orthogonal experiment based on orthogonal test method, By range analysis of sedimentation rate and viscosity at zero external magnetic field, well stability MRF formula was obtained.