Multiphase Characterization of Phase Equilibria in the Tb-Rich Corner of the Co-Cu-Tb System

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27240%2F19%3A10242368" target="_blank" >RIV/61989100:27240/19:10242368 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989100:27360/19:10242368

Výsledek na webu

<a href="https://link.springer.com/article/10.1007/s11669-019-00735-x" target="_blank" >https://link.springer.com/article/10.1007/s11669-019-00735-x</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s11669-019-00735-x" target="_blank" >10.1007/s11669-019-00735-x</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Multiphase Characterization of Phase Equilibria in the Tb-Rich Corner of the Co-Cu-Tb System

Popis výsledku v původním jazyce

In recent years, the grain-boundary diffusion (GBD) and grain-boundary restructuring processes used in manufacturing Nd-Fe-B magnets show promise as procedures that allow one to increase their hysteretic characteristics. The processes are realized by adding various amounts of heavy-rare-earth metals (in the form of hydrides, oxides, intermetallic compounds, etc.) to powder mixtures. The additions decompose or melt during subsequent heat treatment, and their components diffuse into grains and remain within the grain-boundary phase and thus, increase the anisotropy field of the main-magnetic (Nd2Fe14B-based) phase and improve the grain-boundary structure, respectively. In the present study, we consider alloys near the Tb-3(Co0.6Cu0.4) composition as such an addition, which is of importance in designing the microstructure of Nd-Fe-B permanent magnets allowing us to economically alloy them with terbium (via GBD) simultaneously making copper and cobalt parts of the magnet composition. The phase equilibria in the Tb-rich corner of the Co-Cu-Tb system near the Tb-3(Co0.6Cu0.4) composition, which was found to be multiphase, are assessed based on electron microscopy studies, data from electron microprobe, x-ray diffraction, and differential thermal analyses, and from magnetic measurements. A portion of the isothermal section for compositions Tb-40at.% Co-50at.% Cu at 600 degrees C was constructed. The copper solubility in Tb-3(Co,Cu) and Tb-12(Co,Cu)(7), and Co solubility in the Tb(Cu,Co) compound were determined, which are up to 6.5, 14.5, and 10at.%, respectively. The possibility of hydrogenation of the multiphase composition with the formation of TbHx, and fine Co and Cu powders, which are components for diffusion in manufacturing permanent magnets, is demonstrated.

Název v anglickém jazyce

Multiphase Characterization of Phase Equilibria in the Tb-Rich Corner of the Co-Cu-Tb System

Popis výsledku anglicky

In recent years, the grain-boundary diffusion (GBD) and grain-boundary restructuring processes used in manufacturing Nd-Fe-B magnets show promise as procedures that allow one to increase their hysteretic characteristics. The processes are realized by adding various amounts of heavy-rare-earth metals (in the form of hydrides, oxides, intermetallic compounds, etc.) to powder mixtures. The additions decompose or melt during subsequent heat treatment, and their components diffuse into grains and remain within the grain-boundary phase and thus, increase the anisotropy field of the main-magnetic (Nd2Fe14B-based) phase and improve the grain-boundary structure, respectively. In the present study, we consider alloys near the Tb-3(Co0.6Cu0.4) composition as such an addition, which is of importance in designing the microstructure of Nd-Fe-B permanent magnets allowing us to economically alloy them with terbium (via GBD) simultaneously making copper and cobalt parts of the magnet composition. The phase equilibria in the Tb-rich corner of the Co-Cu-Tb system near the Tb-3(Co0.6Cu0.4) composition, which was found to be multiphase, are assessed based on electron microscopy studies, data from electron microprobe, x-ray diffraction, and differential thermal analyses, and from magnetic measurements. A portion of the isothermal section for compositions Tb-40at.% Co-50at.% Cu at 600 degrees C was constructed. The copper solubility in Tb-3(Co,Cu) and Tb-12(Co,Cu)(7), and Co solubility in the Tb(Cu,Co) compound were determined, which are up to 6.5, 14.5, and 10at.%, respectively. The possibility of hydrogenation of the multiphase composition with the formation of TbHx, and fine Co and Cu powders, which are components for diffusion in manufacturing permanent magnets, is demonstrated.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

<a href="/cs/project/LTARF18031" target="_blank" >LTARF18031: Vývoj fyzikálně-chemických a inženýrských základů pro iniciaci inovativní úsporné technologie výroby vysoce výkonných permanentních magnetů na bázi (Nd,R)-Fe-B (R = Pr, Tb, Dy, Ho) s nízkým obsahem kovů vzácných zemin</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Phase Equilibria and Diffusion

ISSN

1547-7037

e-ISSN

—

Svazek periodika

40

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

10

Strana od-do

403-412

Kód UT WoS článku

000474474300007

EID výsledku v databázi Scopus

2-s2.0-85067384509