Title :
Thermal stability and oxidation resistance of HDDR processed Sm-Fe-Ti-B-N bonded magnets
Author :
Tobise, M. ; Shindoh, M. ; Okajima, H. ; Iwasaki, K. ; Tokunaga, M. ; Liu, Z. ; Hiraga, K.
Author_Institution :
Magnetic & Electron. Mater. Res. Lab., Hitachi Metals Ltd., Saitama, Japan
fDate :
9/1/1999 12:00:00 AM
Abstract :
Thermal stability of HDDR processed Sm-Fe-Ti-B-N bonded magnets is investigated in comparison with HDDR processed Sm-Fe-N bonded magnets. Temperature coefficients of Br and iHc of Sm-Fe-Ti-B-N bonded magnet are -0.06%/°C and -0.43%/°C, respectively, in the temperature range of 25 to 100°C range. Irreversible loss of Sm-Fe-Ti-B-N bonded magnet at 100°C is -2.1% and -2.5% respectively after exposure for 2 hrs and 300 hrs. This irreversible loss of Sm-Fe-Ti-B-N is lower than that of Sm-Fe-N which has coercivity 16 kOe. The corrosion resistance of Sm-Fe-Ti-B-N powder is evaluated by measuring increase in oxygen content after exposure at 120°C. It is compared with Sm-Fe-N and Nd-Fe-Co-B powders. Sm-Fe-Ti-B-N powder shows slight increase in oxygen content after exposure at 120°C in air for 300 hrs. It is also found to have good thermal stability and corrosion resistance
Keywords :
boron alloys; coercive force; corrosion resistance; ferromagnetic materials; iron alloys; magnetic leakage; permanent magnets; powder metallurgy; samarium alloys; stoichiometry; thermal stability; titanium alloys; 100 degC; 120 degC; 2 hour; 300 hour; HDDR processed Sm-Fe-Ti-B-N bonded magnets; Sm-Fe-Ti-B-N; coercivity; corrosion resistance; irreversible loss; oxidation resistance; oxygen content; powder; temperature coefficients; thermal stability; Bonding; Coercive force; Corrosion; Electrical resistance measurement; Magnets; Oxidation; Powders; Temperature distribution; Thermal resistance; Thermal stability;
Journal_Title :
Magnetics, IEEE Transactions on
