No. 1149
	Thermal Stability, Applications and Coercivity of High-Performance Permanent Magnets - Evaluation of Long Term Stability of Rare Earth Magnets in a Partially Magnetized State and Investigation on their Applications and Coercivity of the Magnets -
	Sub-committee on high-performance permanent magnets and their�@applications
	Keyword : Nd-Fe-B magnets, Rare Earth bonded magnets, Long term stability, Measurement method, Application of magnets
	Many kinds of high-performance permanent magnets have been used in a wide variety of applications. Circumstances for the use of permanent magnets have become diversified significantly. For example, a partially magnetized state can be seen in ring magnets with radial alignment which are magnetized to radial multi-poles. In this report irreversible flux loss was evaluated for the 2-17 Sm-Co sintered magnets with different coercivity values in a partially magnetized state at elevated temperatures. This evaluation was done by members of the sub-committee. The results are described in Chapter 2. This kind of irreversible flux loss evaluation was also performed for various kind of bonded magnets(Sm-Fe-N, Nd-Fe-B and Nd-Fe-B exchange spring magnets) and is described in Chapter 3. Measurement method for permanent magnet with coercivity higher than 2MA/m is described in chapter 4. Permanent magnet applications for automobiles and small motors were investigated and are described in chapters 5 and 6, respectively. The high coercivity of Co-(Ni, Mn, Y, Cr) spinel ferrite prepared by coprecipitation is reported in Chapter 7. Coercivity and Nucleation of magnetic reversal nuclei in Nd-Fe-B sintered magnets is discussed in Chapter 8.
	©2007. The Institute of Electrical Engineers of Japan