Effects of quenching rate on the phase transformation and magnetic properties of melt-spun Pr8Fe86Bg6 ribbons during annealing

被引：29

作者：

Wang, ZC ^{[1
]}

Zhou, SZ ^{[1
]}

Qiao, Y ^{[1
]}

Zhang, MC ^{[1
]}

Wang, R ^{[1
]}

机构：

[1] Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 2000年 / 218卷 / 01期

基金：

中国国家自然科学基金;

关键词：

melt spun ribbons; phase transformation; nanocomposite magnets; magnetic properties;

D O I：

10.1016/S0304-8853(00)00363-2

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Phase transformations and magnetic properties of overquenched Pr8Fe86B6 ribbons during annealing treatment have been investigated. The as-quenched structure of the ribbons was varied by changing the quenching rate during the melt spinning process. It was found that, depending on their as-quenched structures, the phase transformations of the ribbons during annealing may take place in one of the following sequences: (1) Amorphous phase (Am)+ Pr2Fe14B + alpha-Fe --> Pr2Fe14B + alpha-Fe; (2) Am + alpha-Fe --> Am' + alpha-Fe --> alpha-Fe + Pr2Fe23B3+Pr2Fe14B --> Pr2Fe14B + alpha-Fe; and (3) Am --> Am' + alpha-Fe --> Pr2Fe23B3 + alpha-Fe --> Pr2Fe14B + alpha-Fe. However, for all the ribbons, the microstructure after optimal annealing was found to consist only of two magnetic phases: Pr2Fe14B and alpha-Fe. The optimum magnetic properties (intrinsic coercivity H-ci and remanent polarization J(r)), and the squareness of the demagnetization curves of the annealed ribbons deteriorated drastically with increasing quenching rate of unannealed precursors. This deterioration can be attributed to the formation of a coarser and more irregular microstructure during annealing of the samples initially melt spun with higher wheel speeds, which was confirmed by our TEM observations, analysis of the temperature dependence of coercivity and measurement of irreversible susceptibility. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：72 / 80

页数：9

共 19 条

[1] Nanocrystalline FeNdB permanent magnets with enhanced remanence [J].

Bauer, J ;

Seeger, M ;

Zern, A ;

Kronmuller, H .

JOURNAL OF APPLIED PHYSICS, 1996, 80 (03) :1667-1673

[2] Effect of wheel speed and subsequent annealing on the microstructure and magnetic properties of nanocomposite Pr2Fe14B/α-Fe magnets [J].

Chen, ZM ;

Zhang, Y ;

Hadjipanayis, GC ;

Chen, Q ;

Ma, BM .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1999, 206 (1-2) :8-16

[3] THE MICROSTRUCTURAL AND COMPOSITIONAL INFLUENCE UPON HIREM BEHAVIOR IN ND2FE14B [J].

CLEMENTE, GB ;

KEEM, JE ;

BRADLEY, JP .

JOURNAL OF APPLIED PHYSICS, 1988, 64 (10) :5299-5301

[4]

COEY JMD, 1995, J MAGN MAGN MATER, V140, P1040

[5] PHASE DISTRIBUTION AND COMPUTED MAGNETIC-PROPERTIES OF HIGH-REMANENT COMPOSITE MAGNETS [J].

FISCHER, R ;

SCHREFL, T ;

KRONMULLER, H ;

FIDLER, J .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1995, 150 (03) :329-344

[6] Grain-size dependence of remanence and coercive field of isotropic nanocrystalline composite permanent magnets [J].

Fischer, R ;

Schrefl, T ;

Kronmuller, H ;

Fidler, J .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1996, 153 (1-2) :35-49

[7] Investigation of phase composition and remanence enhancement in rapidly quenched Nd-9(Fe, Co)(85)B-6 alloys [J].

Gabay, AM ;

Popov, AG ;

Gaviko, VS ;

Belozerov, YV ;

Yermolenko, AS ;

Shchegoleva, NN .

JOURNAL OF ALLOYS AND COMPOUNDS, 1996, 237 (1-2) :101-107

[8] Magnetic and microstructural properties of nanocrystalline exchange coupled PrFeB permanent magnets [J].

Goll, D ;

Seeger, M ;

Kronmuller, H .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1998, 185 (01) :49-60

[9]

HADJIPANAYIS GC, 1994, J APPL PHYS, V76, P7065

[10] Magnetic properties of Nd-Fe-B-Cr nanocrystalline composite magnets [J].

Hinomura, T ;

Nasu, S ;

Kanekiyo, H ;

Uehara, M ;

Hirosawa, S .

MATERIALS TRANSACTIONS JIM, 1997, 38 (12) :1106-1115

← 1 2 →