NdFeB磁体表面硅烷薄膜的制备及其性能研究

发布时间：2018-07-05 03:36

  本文选题：烧结NdFeB磁体 + 硅烷转化膜　； 参考：《合肥工业大学》2017年硕士论文

【摘要】：烧结NdFeB磁体自问世以来,以其优异的磁性能而被广泛应用于国民经济的各个领域。但NdFeB磁体的耐蚀性能极差,严重限制了其应用领域的进一步拓展。因此,需要在烧结NdFe B磁体表面添加防护涂层,提高磁体的耐蚀性能。本文采用硅烷化技术对NdFeB磁体进行表面防护处理,在磁体表面制备了硅烷转化膜。为磁体表面防护提供了一种新型环保的暂时性防护措施。采用浸涂法在烧结NdFeB表面制备了硅烷转化膜,利用盐雾试验测试其耐腐蚀性能,进而采用正交试验法对影响硅烷水解、成膜的工艺参数进行了优化,结果表明:硅烷水解的最佳工艺参数是硅烷偶联剂浓度为150 ml/L,醇水比为80:20,水解温度为30℃,水解时间为24 h,PH值为11,硅烷成膜的最佳工艺参数是浸涂时间为2 min,在80℃下预烘烤15 min,固化温度为180℃,固化时间为1.5 h。采用最佳工艺参数在磁体表面制备的硅烷转化膜的耐蚀性能较好,但力学性能较差。为了改善烧结NdFeB磁体表面硅烷转化膜的力学性能及耐腐蚀性能,通过在浸涂溶液中掺杂纳米CeO_2颗粒对硅烷转化膜进行了改性处理,制备了CeO_2/硅烷复合薄膜。采用中性盐雾试验和动电位极化曲线对涂层的耐蚀性能进行了研究,分别采用拉力试验机和显微硬度计对基体与涂层之间的结合力及CeO_2/硅烷复合薄膜的显微硬度进行了测试。结果表明:在NdFeB磁体表面涂覆的CeO_2/硅烷复合薄膜较硅烷转化膜具有更加优异的耐腐蚀性能和力学性能。对在NdFeB磁体表面制备的硅烷转化膜和CeO_2/硅烷复合薄膜的腐蚀机理进行了系统探究,并初步建立了相应的腐蚀模型。为烧结NdFeB磁体表面实现硅烷化防护处理提供了技术支持。
[Abstract]:Sintered NdFeB magnets have been widely used in various fields of national economy because of their excellent magnetic properties. However, the corrosion resistance of NdFeB magnets is very poor, which seriously limits the further development of their application fields. Therefore, it is necessary to add protective coating on the surface of sintered NdFeB magnets to improve the corrosion resistance of the magnets. Silane conversion films were prepared on the surface of NdFeB magnets by silanization. It provides a new kind of temporary environmental protection measures for the surface protection of magnets. Silane conversion film was prepared on the surface of sintered NdFeB by immersion coating method. The corrosion resistance of the film was tested by salt spray test, and the process parameters affecting silane hydrolysis and film formation were optimized by orthogonal test. The results show that the optimum technological parameters of silane hydrolysis are the concentration of silane coupling agent 150 ml / L, the ratio of alcohol to water 80: 20, and the hydrolysis temperature 30 鈩，

本文编号：2098750