Chemical Synthesis of Next Generation High Energy Product Hybrid SmCo Permanent Magnets for High Temperature Applications

Roller-ball milling (RBM) or planetary ball milling (PBM) have been used together with the hydrogen decrepitation (HD) process to produce sintered permanent magnets based on a mixture of Pr16Fe76B8 and Pr14.00Fe63.90Co16.00B6.00Nb0.10 magnetic alloys. Five distinct compositions have been studied comparing low- and high-energy milling. Magnets with a particular composition and prepared using these two routes exhibited similar magnetic properties. Modifications have been carried out in the procedure of the HD stage for PBM in order to guarantee a high degree of crystallographic alignment. Pr15.00Fe69.95Co8.00B7.00Nb0.05 magnets showed the best maximum energy product for both processing routes (~ 247 kJm-3). A significant reduction in the milling time (93%) has been achieved with high-energy processing, the greatest advantage over the low-energy route.

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Effect of microstructure parameter on the energy product in two-phase permanent magnetic materials

Modern Physics Letters B ◽

10.1142/s0217984919500258 ◽

2019 ◽

Vol 33 (03) ◽

pp. 1950025

Author(s):

Reshma Reba Alexander ◽

R. Justin Joseyphus

Keyword(s):

Magnetic Materials ◽

Permanent Magnets ◽

High Energy ◽

Microstructural Parameter ◽

Two Phase ◽

Magnetic Phases ◽

Microstructure Parameter ◽

Energy Product ◽

Effect Of Microstructure

Two-phase permanent magnets with soft and hard magnetic phases are suitable candidates for high energy product permanent magnets. To obtain enhanced energy product, the microstructure has to be optimum and the magnetization and nucleation field has to be as large as possible. The present studies suggest suitable combinations of soft–hard composites that could result in higher energy product. The role of microstructural parameter on the energy product is also presented.

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Microstructure Effects on Creep Behavior of Next Generation of Refractory Alloys for Very High Temperature Applications

10.21236/ada403745 ◽

2002 ◽

Author(s):

Vijay K. Vasudevan ◽

Keith J. Leonard

Keyword(s):

High Temperature ◽

Creep Behavior ◽

Next Generation ◽

Refractory Alloys ◽

Microstructure Effects ◽

Very High ◽

Temperature Applications

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NdFeB/αFe Nanocomposite Permanent Magnets with Enhanced Properties Prepared by Spark Plasma Sintering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.672.229 ◽

2011 ◽

Vol 672 ◽

pp. 229-232

Author(s):

Marian Grigoraş ◽

M. Lostun ◽

Nicoleta Lupu ◽

Horia Chiriac

Keyword(s):

Spark Plasma Sintering ◽

Permanent Magnets ◽

High Energy ◽

Maximum Energy ◽

Maximum Energy Product ◽

Energy Product ◽

Plasma Sintering ◽

Spark Plasma ◽

Energy Ball ◽

Melt Spun Ribbons

Nanocomposite NdFeB/αFe magnets were obtained by spark plasma sintering technique using high energy ball-milled Nd-Fe-B melt-spun ribbons mixed in different weight ratios with Fe commercial powders. The remanence of SPS nanocomposite magnets increases with the Fe powders content from 6.1 for 4 wt.% Fe to 6.4 kG for 5 wt.% Fe, while the estimated maximum energy product is also increased from 9.0 to 10.6 MGOe.

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