铝薄膜对烧结NdFeB磁体耐蚀性能的影响

摘要

Pure Al coating was deposited on sintered NdFeB magnet by direct current (DC) magnetron sputtering to improve the corrosion resistance of magnet. The influences of coating thickness and sputtering power on microstructure and corrosion resistance of Al coating were investigated. The surface morphology of Al coating was characterized by scanning electron microscopy (SEM). The corrosion properties were investigated by potentiodynamic polarization curves and neutral salt spray (NSS) test. The formation of the uniform and compact Al coating is a necessary condition to achieve excellent corrosion resistance. And the optimal corrosion resistance can be obtained in the sample with 6.69μm thick Al coating deposited at 51-82 W.%采用直流磁控溅射的方法在烧结NdFeB磁体表面沉积Al薄膜提高磁体的耐蚀性能。研究膜厚及溅射功率对薄膜结构和耐蚀性能的影响。利用SEM对Al薄膜的微观结构进行分析，并采用动态极化曲线和中性盐雾实验分析Al薄膜耐蚀性能。均匀致密的Al薄膜的形成是获得良好耐蚀性能的必要条件。在51~82 W 溅射功率下制备的6.69μm的Al薄膜具有良好的耐蚀性能。