Research On Performances Of Hybrid Magnetorheological Vibration Isolation Device

Magnetorheological material is a composite material formed by micro-scale soft magnetic particles dispersed in a carrier liquid.In the presence of magnetic field,magnetorheological materials are subjected to magnetorheological effect,their mechanical properties can change rapidly and continuously,the process is highly reversible,which is the focus of research in the field of materials and vibration control.In this paper,a new hybrid laminated magnetorheological material is proposed,magnetorheological fluid(MRF)is encapsulated in magnetorheological elastomer(MRE)to design a high performance vibration isolator based on magnetorheological effect.By changing the current to adjust the stiffness and damping of the magnetorheological material in real time,the vibration isolation range of the vibration isolator can be expanded and better vibration isolation effect can be achieved.According to the influence factors of magnetorheological properties,such as the content of magnetic particles,the choice of matrix materials,etc.,combined with the experimental conditions of our laboratory,MRF,conventional MRE and hybrid laminated magnetorheological materials were prepared by using carbonyl iron powder,silicone rubber and silicone oil were used as main materials for additives at room temperature.MRE was prepared from carbonyl iron powder and silicone rubber,MRF was prepared out of carbonyl iron powder and dimethyl silicone oil.Hybrid laminated magnetorheological materials with MRE and MRF in the inner package were prepared as well.The formation process of particle chain column structure of magnetorheological fluid was observed by using super depth 3D high speed microscope and electron microscope.ANSYS Workbench was used to analyze the magnetic flux lines flowing through the magnetorheological materials,the experimental platform was designed.Combined with universal material testing machine and other related equipment and test methods,the dynamic compression performance and maximum bearing capacity failure test of anisotropy and isotropic magnetorheological elastomer were carried out,and many mechanical properties of magnetorheological materials,such as compression elastic modulus,maximum bearing capacity and so on,were analyzed.According to the relevant principles of magnetic circuit design,a vibration isolation device based on compression mode for magnetorheological materials was designed,the overall structure of the vibration isolation device was designed,processed and assembled.According to the target magnetic field strength,the number of turns of the excitation coil is determined through theoretical calculation,the magnetic field intensity and magnetic flux line distribution across the designed vibration isolation device were simulated and analyzed by using ANSYS finite element software.The results show that the magnetic field intensity in the vibration isolator reaches 780.85mT,and the magnetic induction line distribution is reasonable.The vibration isolation test platform is built,and the vertical exciting force is produced by the electromagnetic vertical vibration of test platform.The acceleration sensor and acquisition card are used to realize the real-time data acquisition.Conventional MR elastomer and hybrid laminated MR materials are installed in the vibration isolation device,respectively,the vibration isolation performance of the vibration isolation device is tested and analyzed by adjusting different currents and different excitation frequencies.Experimental results show that the conventional MRE vibration isolation device and the hybrid laminated magnetorheological material vibration isolation device both have good vibration isolation effect.The vibration attenuation rate of the hybrid laminated magnetorheological(MRE)vibration isolator is much higher than that of the conventional MRE after the excitation current is applied.;under the same excitation current,the greater the excitation frequency,the greater the vibration acceleration.Compared with MRE isolator,hybrid MRf isolator has a wider vibration isolation range and better vibration isolation effect.