Magnetic and structural properties of rapidly quenched Nd-Fe-Co-Ge-B alloys / Beitollahi A.,Gholamipour R.,Marghusian V. K.,Andreev S. V.,Bogatkin A. N.,Duragin S. S.,Kozlov A. N.,Kudrevatykh N. V.,Bogdanov S. G.,Pirogov A. N. // PHYSICS OF METALS AND METALLOGRAPHY. - 2006. - V. 102, l. 1. - P. S24-S31.

ISSN/EISSN:

0031-918X / нет данных

Type:

Article

Abstract:

We have studied the structure and magnetic properties of some rapidly quenched and subsequently annealed alloys prepared by centrifugal method with a composition (in wt \%) Nd(29.5), Co( 6), B(1.1), Ge (x), Fe( balance) with x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0 ( wt \%) for Ge. Based on X-ray diffraction (XRD),elastic neutron diffraction, and small-angle neutron scattering ( SANS), the formation of partially crystallized main hard magnetic 2: 14: 1 ( F) phase in the amorphous matrix was detected for all as-spun samples. The size of the clusters formed for the sample with 1 wt \% Ge determined based on SANS profiles was about 10 nm. It was shown that the addition of Ge shifts the maximum crystallization peak of the main 2: 14: 1 phase to higher temperatures. The variation of the magnitudes of different magnetic parameters such as H-i(c) and M-s versus Ge concentration for as-spun samples can be possibly related to the different rate of crystallization of the 2: 14: 1 phase formed. Further, for the samples doped with 0.8 and 1.0 wt \% Ge and annealed at 760 C for 5 min the formation of some extra phases such as Nd5Ge3, NdFe2, NdB4, as well as a - Fe was detected by XRD. The magnetic measurements carried out using a vibrating-sample magnetometer (VSM) for these samples also supported the XRD data obtained. While the highest values of coercivity H-i(c) = 772 kA/m were obtained for the annealed samples without Ge, the highest value of sigma(r) = 69 emu/g was also obtained for the samples substituted with 0.8 wt \% Ge without an appreciable reduction in iHc.

Author keywords:

PERMANENT-MAGNETS; COERCIVITY; HYDROGEN

DOI:

10.1134/S0031918X06140067

Web of Science ID:

ISI:000248918300006

Соавторы в МНС:

Другие поля

Поле	Значение
Month	DEC
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
Keywords-Plus	PERMANENT-MAGNETS; COERCIVITY; HYDROGEN
Research-Areas	Metallurgy \& Metallurgical Engineering
Web-of-Science-Categories	Metallurgy \& Metallurgical Engineering
ResearcherID-Numbers	Pirogov, Alexander/K-8115-2013 Bogdanov, Savva/K-1613-2013
ORCID-Numbers	Pirogov, Alexander/0000-0001-7321-1245 Bogdanov, Savva/0000-0003-2327-1180
Number-of-Cited-References	20
Usage-Count-Since-2013	5
Journal-ISO	Phys. Metals Metallogr.
Doc-Delivery-Number	202QO