Preparation Of Magnetorheological Elastomer And Simulation And Experimental Studies On Its Application For Vehicle Vibration Reduction

Magnetorheological elastomer (MRE) is a smart material, which is controllable, reversible, and fast responsive in its mechanical, electromagnetic and other properties. As such, it has broad application prospects, such as being used for damping, for vibration and noise control, and so on. Regardless of this situation, however, it is still necessary for further research and development on its unique properties and applications due to the fact that the material is relatively new comparing with other smart materials.Presently, most of the conventional vehicle suspension systems are mainly composed of elastic and rigid components, whose relevant properties are generally fixed, resulting in their vibration reduction capability to be non-adjustable to varying road conditions. It would be of great significance if a new method could be found to replace or improve the existing vehicle suspension systems, so as to make the damping effect adjustable to road conditions.Taking into account both of the above situations, this thesis attempts to apply MREs for vehicle vibration reduction. It starts by investigating the method for preparation of MREs, which is done by designing a mold adjustable for varied thicknesses, trying the constituent materials with different proportions, and measuring the static and dynamic mechanical properties of the developed MREs. Eventually, the MREs with the desired mechanical properties are selected for further research. After that, a 1/4 model of vehicle vibration reduction system employing MREs is established, by applying the theory of vibration and by studying the existing vehicle suspension damping systems. The equivalent stiffness and damping of the MREs within the context of vehicle vibration reduction system are calculated by exploiting the dynamic mechanical properties of the MREs. A simulation study on the vibration reduction effect is subsequently carried out using this model.Based on the results from the above study, a test rig of the MRE-based vehicle vibration reduction system is developed, where two acceleration sensors are employed to measure the effect of vibration reduction. This is done by comparing the voltage readings from the two sensors before and after the MRE-based vibration reduction system is activated. Through both experimental study and simulation study,those variables that influence the vibration reduction effect more prominently are identified, and the vibration reduction effect influenced by these variables is discussed.The thesis ends with a conclusion on the results from both the simulation study and the experimental study. It also proposes the strategies for improving these studies and the directions for further research. The prospects of applying MREs in vehicle vibration reduction and other potential areas are also analyzed.