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Magnetic Abrasive' dissertation">Magnetic Abrasive Finishing technology Finishing a promising new technology, with the design of low-cost, high processing efficiency, easy operation, low environmental pollution, less energy consumption, easy automation, etc., therefore, Magnetic Abrasive Finishing technology constantly get development and production has been widely applied. Magnetic Abrasive Finishing the key as the magnetic abrasive abrasive, this paper analyzes the the magnetic abrasive abrasive grinding mechanism, and Magnetic Abrasive Finishing on the basis of magnetic abrasive performance requirements. In the formation of the grinding pressure, the composition of the component of the magnetic abrasive on the basis of the analytical study of the structural shape and the production method of the magnetic abrasive atmospheric solid phase sintering of the magnetic abrasive method. In conventional sintering method based on high-temperature inorganic binder instead of titanium, molybdenum, and other precious metal bonded components, and iron powder surface coating by sol - gel method SiO2 pressureless sintering atmosphere protected prepared a series of magnetic abrasive powder in the electric furnace. Studied the influence of sintering temperature, sintering time, the pressing pressure, the ratio of raw materials, the kind of the ferromagnetic phase, phase particle size of the abrasive grains and the sintering atmosphere on the magnetic abrasive performance, and to determine the final parameters of the experiment, and in this condition prepared series magnetic abrasive. Thermal field emission scanning electron microscope (SEM) and X-ray energy dispersive spectroscopy (EDS) characterization of magnetic abrasive morphology and elemental composition of magnetic abrasive phase composition using X-ray diffraction (XRD), and through experimental magnetic abrasive grinding performance tests and durability. The experimental results show that the magnetic abrasive of the sintering method is mainly composed of α-Fe, Al2O3, Fe2O3, AlFeO3 etc. phase composition, and its shape is irregular edged structure; magnetic abrasive having good abrasive effect and longer duration of use, grinding workpiece surface roughness can be achieved 0.12μm, the use of time up to 24 min. In addition, we as the raw material ferrosilicon powder, white fused alumina and high temperature resistant inorganic binder explore experimental study of sintering temperature, sintering time and pressing pressure, combined with the degree of magnetic abrasive, using optical microscope, scanning electron microscope and X-ray energy dispersive instrument intrinsic magnetic abrasive morphology and elemental composition. The experimental results indicate that the sintering temperature, sintering time and pressing pressure and after sintering have a close relationship of the degree of binding of the magnetic abrasive. The higher the sintering temperature, sintering time is longer, the better the binding position of the magnetic abrasive, the sintering temperature of not lower than 1200 ° C, the sintering time is not less than 5 h, in order to guarantee to obtain a good bonding state between the corundum powder with iron fume; help ferrosilicon powder and corundum powder bonding between situation compacting pressure, molding to suppress the greater the pressure, combined with the better.
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