Investigation of Grain Boundary Compositions and Magnetic Properties of Hot-Worked Nd_{18}Tb_1Fe_{66.5}Co_5Al_{1.5}B_8 Magnets

• Authors: G. Sadullahoğlu , B. Altuncevahir , A. Okan Addemir
• Languages of publication: EN

Abstracts

EN

Magnetic properties which are related to the compositions on the grain boundaries of the NdFeB permanent magnets were studied at different hot working temperatures applied to the cast Nd_{18}Tb_1Fe_{66.5}Co_5Al_{1.5}B_8 ingots. Since the addition of Al caused the formation of hard magnetic μ phase between the magnetic NdFeB crystals after the pressing 800C H_{c} value increased to the highest value of 8.21 kOe. According to the SEM micrographs and EDS analysis, the increase in pressing temperature, the atomic ratios in the NdFeAl compositions approached to hard magnetic μ phase with the increase in pressing temperature and its exact composition was obtained in the sample hot deformed at 800°C. Although the secondary μ phase with a high melting temperature is detremental to the alignment of c axis of the magnetic NdFeB grains along the pressing direction, we found that the magnetic properties of the magnets improve due to the presence of this hard magnetic phase on the grain boundaries.

Keywords

EN

75.50.Ww; 75.50.Vv; 75.50.Bb

Discipline

• 75.50.Vv: High coercivity materials
• 75.50.Bb: Fe and its alloys
• 75.50.Ww: Permanent magnets(for magnets, see 07.55.Db in instruments)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2013
• Volume: 123
• Issue: 2
• Pages: 233-234

Dates

published

2013-02

Contributors

author

G. Sadullahoğlu

• Istanbul Technical University, Metallurgical and Materials Engineering, 34469, Maslak, Istanbul, Turkey

author

B. Altuncevahir

• Istanbul Technical University, Physics Engineering, 34469 Maslak, Istanbul, Turkey

author

A. Okan Addemir

• Istanbul Technical University, Metallurgical and Materials Engineering, 34469, Maslak, Istanbul, Turkey

References

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Identifiers

DOI

10.12693/APhysPolA.123.233