Abstract
We investigated the effects of Al/Cu co-doping on the magnetic and microstructural properties of a Nd-Fe-B sintered magnet. In particular, the structural and compositional changes of Cu-dissolved Nd-rich (Cu-rich) triple junction phase (TJP) and grain boundary phase (GBP) experienced upon Al/Cu co-doping were intensively analyzed. Al was selectively dissolved into the Culow-rich phases (B phase, 3–15 at.% Cu) other than the Cuhigh-rich phases (A phase, 20–45 at.% Cu). The B phase with an h-Nd2O3 structure was transformed to the C phase (Al-dissolved Culow-rich phases) with a c-Nd2O3 structure upon Al dissolution. In addition, the continuity of C GBP was improved and the Fe content of C GBP was reduced (25 → 5 at.% Fe). As a result, the coercivity (Hc) of the Al/Cu co-doped magnet was higher than that of a Cu-doped magnet. The critical role played by Al in improving the magnetic properties and microstructure of the Al/Cu co-doped magnet was elucidated. The detailed mechanism for the Hc enhancement of the Al/Cu co-doped magnet was discussed based on the results.
| Original language | English |
|---|---|
| Pages (from-to) | 200-207 |
| Number of pages | 8 |
| Journal | Acta Materialia |
| Volume | 133 |
| DOIs | |
| Publication status | Published - 2017 Jul 1 |
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Keywords
- Coercivity
- Grain boundaries
- Metastable phases
- Microstructures
- Nd-Fe-B sintered magnet
- Triple junctions
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Polymers and Plastics
- Metals and Alloys
Cite this
Effects of Al/Cu co-doping on crystal structure and chemical composition of Nd-rich phases in Nd-Fe-B sintered magnet. / Kim, Tae Hoon; Lee, Seong Rae; Bae, Kyoung Hoon; Kim, Hyo Jun; Lee, Min Woo; Jang, Tae Suk.
In: Acta Materialia, Vol. 133, 01.07.2017, p. 200-207.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Effects of Al/Cu co-doping on crystal structure and chemical composition of Nd-rich phases in Nd-Fe-B sintered magnet
AU - Kim, Tae Hoon
AU - Lee, Seong Rae
AU - Bae, Kyoung Hoon
AU - Kim, Hyo Jun
AU - Lee, Min Woo
AU - Jang, Tae Suk
PY - 2017/7/1
Y1 - 2017/7/1
N2 - We investigated the effects of Al/Cu co-doping on the magnetic and microstructural properties of a Nd-Fe-B sintered magnet. In particular, the structural and compositional changes of Cu-dissolved Nd-rich (Cu-rich) triple junction phase (TJP) and grain boundary phase (GBP) experienced upon Al/Cu co-doping were intensively analyzed. Al was selectively dissolved into the Culow-rich phases (B phase, 3–15 at.% Cu) other than the Cuhigh-rich phases (A phase, 20–45 at.% Cu). The B phase with an h-Nd2O3 structure was transformed to the C phase (Al-dissolved Culow-rich phases) with a c-Nd2O3 structure upon Al dissolution. In addition, the continuity of C GBP was improved and the Fe content of C GBP was reduced (25 → 5 at.% Fe). As a result, the coercivity (Hc) of the Al/Cu co-doped magnet was higher than that of a Cu-doped magnet. The critical role played by Al in improving the magnetic properties and microstructure of the Al/Cu co-doped magnet was elucidated. The detailed mechanism for the Hc enhancement of the Al/Cu co-doped magnet was discussed based on the results.
AB - We investigated the effects of Al/Cu co-doping on the magnetic and microstructural properties of a Nd-Fe-B sintered magnet. In particular, the structural and compositional changes of Cu-dissolved Nd-rich (Cu-rich) triple junction phase (TJP) and grain boundary phase (GBP) experienced upon Al/Cu co-doping were intensively analyzed. Al was selectively dissolved into the Culow-rich phases (B phase, 3–15 at.% Cu) other than the Cuhigh-rich phases (A phase, 20–45 at.% Cu). The B phase with an h-Nd2O3 structure was transformed to the C phase (Al-dissolved Culow-rich phases) with a c-Nd2O3 structure upon Al dissolution. In addition, the continuity of C GBP was improved and the Fe content of C GBP was reduced (25 → 5 at.% Fe). As a result, the coercivity (Hc) of the Al/Cu co-doped magnet was higher than that of a Cu-doped magnet. The critical role played by Al in improving the magnetic properties and microstructure of the Al/Cu co-doped magnet was elucidated. The detailed mechanism for the Hc enhancement of the Al/Cu co-doped magnet was discussed based on the results.
KW - Coercivity
KW - Grain boundaries
KW - Metastable phases
KW - Microstructures
KW - Nd-Fe-B sintered magnet
KW - Triple junctions
UR - http://www.scopus.com/inward/record.url?scp=85019954414&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85019954414&partnerID=8YFLogxK
U2 - 10.1016/j.actamat.2017.05.046
DO - 10.1016/j.actamat.2017.05.046
M3 - Article
VL - 133
SP - 200
EP - 207
JO - Acta Materialia
JF - Acta Materialia
SN - 1359-6454
ER -