【作者】 黄玉红；

【导师】 赵增典；

【作者基本信息】 山东理工大学 ， 应用化学， 2010， 硕士

【摘要】 磁力研磨加工技术是一种很有前途的光整加工新工艺,具有设计成本低、加工效率高、操作容易、环境污染低、能源消耗少、容易自动化等优点,因此,磁力研磨加工技术不断获得发展,并在生产中得到广泛应用。而作为该技术磨具的磁性磨料是磁力研磨加工的关键所在,为此,本文分析了磁性磨料磨粒的磨削机理,并在此基础上提出了磁力研磨加工对磁性磨料性能的要求。在对研磨压力的形成、磁性磨料的组成成分、结构形状及磁性磨料的制备方法分析研究的基础上,提出了常压固相烧结制备磁性磨料的方法。在传统烧结法的基础上,我们采用高温无机粘结剂替代钛、钼等贵重金属粘结组分,并通过溶胶-凝胶法在铁粉表面包覆SiO2,在无气氛保护的常压烧结电炉中制备了一系列磁性磨料。研究了烧结温度、烧结时间、压制压力、原料配比、铁磁相种类、磨粒相粒径和烧结气氛对磁性磨料性能的影响,确定了最终的实验参数,并在此条件下制备了一系列磁性磨料。采用热场发射扫描电子显微镜(SEM)和X射线能量色散谱(EDS)表征了磁性磨料的形貌和元素组成,采用X-射线衍射仪(XRD)研究了磁性磨料的物相组成,并通过实验对磁性磨料进行了研磨性能测试和耐用度分析。实验结果表明,烧结法制备的磁性磨料主要由α-Fe、Al2O3、Fe2O3、AlFeO3等相组成,其形状多为不规则的棱状结构；磁性磨料具有良好的研磨效果和较长的使用时间,研磨工件的表面粗糙度可达到0.12μm,使用时间可达24 min以上。另外,我们以硅铁粉、白刚玉及耐高温无机粘结剂为原料进行了探索实验,研究了烧结温度、烧结时间和压制压力对磁性磨料结合度的影响,采用金相显微镜、扫描电子显微镜和X射线能量色散仪表征了磁性磨料的形貌和元素组成。实验结果表明,烧结温度、烧结时间及压制压力与烧结之后磁性磨料的结合度都有密切的关系。烧结温度越高、烧结时间越长,磁性磨料的结合状况越好,烧结温度不要低于1200℃,烧结时间不要低于5 h,以保证刚玉粉与铁硅粉之间得到良好的结合状态；压制压力有助于硅铁粉与刚玉粉之间的结合状况,成型压制压力越大,结合状况越好。更多还原

【Abstract】 As a new promising process, magnetic abrasive finishing(MAF) has achieved great development and been widely used due to the low design cost, high finishing efficiency, easy operation, low pollution, low energy consumption, easy automation, etc. As grinding tool, magnetie abrasive is the key of magnetic abrasive finishing, so in the paper we analysed the grinding mechanism of magnetic abrasive particles and based on the work,we brought forward performance requirerment of magnetic abrasive for magnetic abrasive finishing. In the paper, following items on magnetic abrasive were analyzed:grinding pressure, composition, structure, shape and the preparation method of magnetic abrasive, then conventional solid-state sintering method of magnetic abrasive was brought forward.In the paper, based on the traditional sintering method, using high-temperature inorganic binder instead of titanium, molybdenum and other precious metals bonded components, and iron powder surface was coated with SiO2 by Sol-gel method, a series of magnetic abrasive was prepared in the absence of climate protection. Then we studied the effect of sintering temperature, sintering time, suppressing pressure, ratio of raw materials, ferromagnetic phase type, abrasive particle size and sintering atmosphere on properties of magnetic abrasive, then the proper experimental parameters were determined, and in this condition, a series of magnetic abrasive was prepared. Thermal field emission scanning electron microscopy and X-ray energy dispersive spectroscopy were used to characterize the morphology and elemental composition, X-ray diffraction was used to study the phase composition. We also test the performance of magnetic abrasive grinding and analysed the durability. Experimental results indicated that, the magnetic abrasive was mainly composed of a-Fe, Al2O3, Fe2O3, AlFeO3, which were mainly irregular polyhedral particles. All the magnetic abrasive prepared had good polishing ability and long using time, and the surface roughness of the grinding sample can reach 0.12μm and the using time is up to 24 min.In addition, with ferrosilicon powder, corundum powder and high temperature inorganic binder were used as the raw materials, the magnetic abrasive has been prepared. We studied the influence of sintering temperature, sintering time, suppressing pressure on the binding degree of magnetic abrasive, and optical microscope, scanning electron microscopy and energy dispersive X-ray instrument were used to characterize the morphology and elemental composition. Experimental results show that the sintering temperature, sintering time and suppressing pressure are closely related to the binding degree of magnetic abrasive. The higher sintering temperature or the longer sintering time are, the better combination conditions of magnetic abrasive will be. The sintering temperature should be higher than 1200℃, sintering time should be longer than 5 h, to ensure that corundum powder remained high bond strength with ferrosilicon powder. Suppressing pressure is helpful to the combination state of ferrosilicon powder and alumina powder, the greater suppressing pressure is, the better combination conditions will be.更多还原