Details

Autor(en) / Beteiligte

• Song, Y. W.
• Zhang, H.
• Yang, H. X.
• Song, Z. L.

Titel

A comparative study on the corrosion behavior of NdFeB magnets in different electrolyte solutions

Ist Teil von

• Materials and corrosion, 2008-10, Vol.59 (10), p.794-801

Ort / Verlag

Weinheim: WILEY-VCH Verlag

Erscheinungsjahr

2008

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Sintered NdFeB magnets possess excellent magnetic properties. However, the corrosion resistance property of NdFeB is very poor due to its multiphase microstructure consisting of matrix phase Nd2Fe14B, Nd‐rich phase, and B‐rich phase. The corrosion behavior of NdFeB magnets in sodium hydroxide (NaOH), sodium chloride (NaCl), nitric acid (HNO3), and oxalic acid (H2C2O4) solutions was investigated by immersion and electrochemical tests. HNO3is the strongest corrosive electrolyte compared with the other three solutions. The increase in HNO3concentration can accelerate the corrosion of NdFeB magnets. NaCl belongs to medium corrosion electrolyte. A NaCl concentration of 0.5 M shows the severest corrosive feature in comparison with other concentrations of NaCl solution. NdFeB hardly suffers corrosion in NaOH and H2C2O4solutions owing to the formation of passivation films on the surface of magnets. Based on the corrosion behavior of NdFeB in different electrolytes, the possible corrosion mechanisms are discussed.