烧结钕铁硼在各种酸介质中的腐蚀研究

Corrosion Behavior of Sintered NdFeB Magnets in Various Acid Solution

摘要:

研究了烧结钕铁硼在硝酸、盐酸、硫酸、磷酸及草酸介质中的腐蚀特征。采用动电位扫描及腐蚀失重测试分析了腐蚀行为和特征，采用AFM和SEM观察了酸腐蚀后的NdFeB表面微观形貌。结果表明，烧结钕铁硼在盐酸及硫酸介质中的腐蚀速率最大，在磷酸及草酸介质中呈钝化态，在硝酸中的边缘腐蚀较严重，对磁体的宏观尺寸破坏较大，在各种酸中腐蚀后的微表面都更粗糙了。

Abstract:

The corrosion behavior of sintered NdFeB in nitric acid hydrochloric acid,vitriol,phosphate and oxalic acid was studied.Potentiodynamic polarization curves and corrosion rate of sintered NdFeB in various solutions were tested.The surface morphology of sintered NdFeB corroded were investigated by means of SEM and AFM.The results indicate that corrosion of sintered NdFeB in hydrochloric acid and vitriol is most serious among all acid,and sintered NdFeB is passivated in phoshate and oxalic acid.The brim of sintered NdFeB is corroded rather seriously and the micro dimension was destroyed greatly in nitric acid.Every surface of magnet corroded by above acid becomes coarse.