Process analysis of MgO film on NdFeB magnet by sol-gel method

摘要

The present paper is a report on sol-gel synthesis of crystalline magnesium oxide on NdFeB magnet, using nonalkoxide precursor chemicals and additive of collodion as template. The decomposition of the precursor and subsequent formation of MgO film on NdFeB magnet was simulated by flow chart which is confirmed by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and theoretical calculation. X-ray diffraction analysis pointes out that the phases present at 350°C is periclase MgO and the crystallite size of MgO grows as the heat treatment temperature increases. The formation process of MgO is verified by FTIR. The component of film on the NdFeB magnet is mainly magnesium oxide, which is also well crystallised and transparent. The corrosion tests indicate that the film is anticorrosion for NdFeB magnet.