Jixie qiangdu (Jan 2017)
STUDY ON THE MICROMECHANICAL MODEL OF FORCE-MAGNETIC COUPLING FOR FERROGEL MATERIALS
Abstract
The ferrogel sample was prepared by carbonyl iron powder as conductive phase and vulcanized silicone rubber as matrix. The microstructure and mechanical properties of the sample are analyzed and tested by using X ray diffractometer（ XRD）and MTS testing machine. Based on the analysis of the microstructure and morphology features and the compression performance data,a stress-magnetization coupled model was established in accordance with the magnetic interaction between particles,and some factors influencing on magneto-induced effect and macroscopic response of ferrogel are analyzed theoretically,including the magnetic particle content,size ratio,magnetic field strength and compress strain etc. The results show that the roughness has little effect on the average peak shear stress when compress strain is low,while with the increase of the normal stress,the magneto-induced effect comes into play. And the magneto-induced compressive modulus of ferrogel tends to increase with the increment of the magnetic particle content,size ratio,magnetic field strength and compression strain. If the mass fraction of the magnetic granular in ferrogel is more than 70wt%,the ductility and fracture toughness of ferrogel composites would be notably reduced. In order to gain ferrogel composites with excellent magneto-induced effect,the the optimized combination of the selected factors would be employed were in the preparation of ferrogel materials. This provides theoretical help for material production and optimization of functions and behaviors for the device.
