Title :
A high performance Nd-Fe-B magnet with improved corrosion resistance
Author :
Kim, A.S. ; Camp, F.E.
Author_Institution :
Crucible Materials Corp., Pittsburgh, PA, USA
fDate :
9/1/1992 12:00:00 AM
Abstract :
Various alloy modifications have been examined in order to improve the corrosion resistance and temperature stability of Nd-Fe-B magnets. Such alloy modifications are generally accompanied by a reduction in magnetic properties. Therefore, modifications which satisfy the criteria for both high magnetic properties (Br and H cj) and good corrosion resistance are desired. It is found that when the three elements Co, Al, and Zr are simultaneously substituted for Fe in Nd-(Dy)-Fe-B magnets, both the corrosion resistance and the magnetic properties are significantly improved. The optimum Zr content is about 1.0 wt.%. A long-term (100 days) corrosion test in an autoclave environment has not disintegrated or attacked the surface of some Nd-(Dy)-Fe-Co-B-Al-Zr magnets. This indicates that corrosion-free high-performance magnets can be readily produced from Nd-(Dy)-Fe-Co-B-Al-Zr
Keywords :
alloying additions; boron alloys; coercive force; corrosion; ferromagnetic properties of substances; iron alloys; neodymium alloys; permanent magnets; remanence; Nd-Fe-Co-Al-Zr-B; alloy modifications; autoclave environment; coercive field; corrosion resistance; corrosion-free high-performance magnets; high performance Nd-Fe-B magnet; long term corrosion test; magnetic properties; remanence; temperature stability; Corrosion; Magnetic materials; Magnetic properties; Niobium; Powders; Stability; Surface resistance; Temperature; Testing; Zirconium;
Journal_Title :
Magnetics, IEEE Transactions on
