1Element Strategy Initiative
Center for Magnetic Materials(ESICMM)
Director-general
Satoshi Hirosawa
National Institute for Materials ScienceTsukuba, Japan

The quest for high energy-density permanent magnets
Development of permanent magnets
600

@RT

Nd-Fe-B(BH)max (kJ/cm3)

500
400

Hard Disc
Drives

Sm‐Co

200

Bonded Nd‐Fe‐B
BondedSm‐Co

Alnico & FeCrCo0
1900

http://www.meank-magnet.com

Nd-Dy-Fe-B
with μ0Hc > 3T

300

100

Automobile
parts(KS, MK, NKS)

Ferrites
1925

1950

1975

Year

2000

HEV, EV2025

https://www.google.co.jp

High coercivity
Nd-Dy-Fe-B
https://automobiles.honda.com/

2

Further Requirements from Society

3Permanent magnets for the next generation applications

Dy-free Nd-Fe-B (realized by2016)
Permanent magnet withsuperb performance at hightemperatures
Emerging applications
Quest for development of new
permanent magnet free fromcritical elements

Global Wind Report 2016

Ehang
https://jp.techcrunch.com/

NASA’s X-57 Maxwell
http://findmarketreport.com/nasasx-57-maxwell-the-agencys-firstall-electric-x-plane-and-firstcrewed-x-planed-in-twodecades/7774/

Our Goals:
Goal 1: Realization of ultimate permanent magnetmaterials
Goal 2: Realization of permanent magnet materialsbased on new Fe-rich compositions
Goal 3: Establishment of basic science of
permanent magnet materials
Goal 4: Dissemination and transfer of ESICMM’s
outputs into industry.

4Topics: Generation and control of coercivity
A basic ingredient for
generating coercivity: Barriers!

ESICMM studies:
Crystal structure and magnetic
properties of main phaseof sub-phases
Grain boundary and interfaces
Theory of coercivity
Thermodynamics

Main phase

Sub-phase acting as
magnetic barrier

5

ESICMM6

The core research center forpermanent magnet
in the Element Strategy Initiative
under auspices of MEXT since 2012Industrial Advisors

fromShinEtsu
TDK
Hitachi Metals
Daido Steel
Aichi Steel
Toyota
Hitachi

13 member institutions
18 PIs
JAISTTohoku GakuinUniversityTohoku University
Thins films
Materials synthesis
Coercivity analyses

Materials informatics

JASRI
SPring-8
KyushuUniversity

Core Institution (HQ)
Microstructure analysis, Synthesis,
1at principles calculations,
Micromagnetic simulations

Kyoto University

Synchrotron X-ray
analysis

Synthesis ofnanoparticles

AIST 1st principles andmaterials informatics

Electronholography

KEK

Nagoya University Tokyo Institute
Phase-field analysis

University of Hyogo
Thermodynamics

Neutron & X-ray analysis

The Universityof Tokyo, ISSP

Computational
material science
Atomistic coercivity theoryof Technology
1st principles largescale computationand thermodynamics

http://www.nims.go.jp/research/ESICMM

Theoretical searchof new matter

Head Office

S. Tsuneyuki(ISSP)
Common Platform

Y. Gohda(TITech)First-principles
structural studies

S. Hirosawa
Directorgeneral

H. Tsuchiura(Tohoku Univ.)
Theoretical study ofcoercivity

S. Miyashita(ISSP)
Statistical physics
of coercivity

C. Mitsumata
Planning
Manager

T. Tadano

Thermodynamics

Computationalphase diagrams

H. Akai (IPPS)
Y. Murakami (KEK)
T. Oguchi (Osaka Univ.)
K. Ozaki (AIST/MagHEM)
A. Sakuma (Tohoku Univ.)
J. Suzuki (J-PARC)
M. Takata (IMRAM)

K. Hono(NIMS)

S. Sugimoto

Multi-scale-multiaspect analyses

T. Nakamura(JASRI)
Synchrotron X-rayanalyses

K. Ono(KEK)
Neutron and X-rayanalyses(Tohoku Univ.)

First-principles
lattice dynamics(NIMS)

Y. Enomoto (Hitachi)
T. Iriyama (Daido Steel)(alphabetical）
C. Mishima (Aichi Steel）
H. Nakamura (Shin-Etsu)(Industry)T. Nishiuchi (Hitachi Met.)(Academia) M. Sagawa (NDFEB）
T. Shoji (Toyota)K. Suzuki (TDK)S. Okamoto(NIMS)

T. AbeAdvisors

T. Koyama(Nagoya U.)
Phase-field
analysis

Magnetization
process

K. Sodeyama(NIMS)
Materials
informatics

Synthesis Group(AIST)

Principal Investigators 18PI (including 3GL and 6 PI from NIMS)

Analysis Group

Theory GroupT. Miyake(Tohoku Univ.)
Novel multi-phasemagnetic materials

T. Teranishi(Kyoto Univ.)
Synthesis of magnetic
meso particles

YK. Takahashi(NIMS)
Thin film synthesisof novel materials

T. Ohkubo(NIMS)
Synthesis of bulk
magnetic materials

H. Nakamura(Kyoto Univ.)
Synthesis andanalysis of ferrites

7

Target materials for ultimate permanent magnet
Selected groups of hard magnetic materials
after screening research (2012 -2016)

1‐122.5L23)
0‐FeCo Zr
Sm(Sm0.92Zr0.18)(Fe0.8Co0.2)120.92
0.18(Fe0.8Co0.2)122

Sm(Fe0.8Co0.2)12 ) 2)
Sm(Fe
Sm(Fe0.8Co0.2)120.8Co
0.2 12

R=Nd or Sm2)0.90.1)12Sm(Fe0.9Co0.1)12

SmFe12
SmFe12

NdFe12N
NdFe N1)

L10‐FeNi
L10‐FeNi

12

Nd2Fe14B

2‐14‐1

1.5
NdFe11TiN

Sm2Fe17N3CeCe2Fe14B
2Fe14B

10.5 ●

Sm2Co17Sm
2Co17

Dy2Fe14B

A(Fe-Co)12O191) Y. Hirayama et al. Scr. Mat. 95 (2015) 702) Y. Hirayama et al. Scr. Mat. 138 (2017) 623) P. Tozman et al. Acta Mater. 178 (2019) 114

00

Fe or Co

Sm(FeSm(Fe0.9Co0.1)Co
12Fe(Nd-Dy)2Fe14B

Spontaneous Magnetization（T）

Sm0.74Zr0.26(Fe0.8Co0.2)123)(Sm0.74Zr0.26)(Fe0.8Co0.2)120.02

0.04

0.06

0.08

Atomic fraction of RE

0.1

0.120.14

8

9Development toward “ultimate Nd-Fe-B”

Easy direction

 Grain-boundary-infiltration process to hot-deformed Nd-Fe-B
 Dy-free Nd-Fe-B-Co-Ga with 2 tesla coercivity at RT (suitable up to c.a, 150°C)
 Superb performance at 150 °C with Nd60Tb10Cu30-infiltration alloy
LRE

R‐rich low‐Tf alloy+ HRE

Ferromagnetic
coupling between
Nd2Fe14B grains(b)Dy-free Target(2016)@ 150°C

Infiltration
Magnetic
decoupling
Diffusion
Cladding withmagneticallyharder shells
Fine-grained (𝐷200 nm) Nd-Fe-B

J. Li et al. Acta Mater. 161 (2018) 171-181.

Discovery of new 1-12-type compounds
Map of hard magnetic compound in 2012
25.0

Anisoropy field Hk [MA/m]Room temp.

BeyondNd2Fe14B

Sm2Fe17N3

20.0
Tb2Fe14B

15.0
Dy2Fe14B

Nd2Fe14B

YCo5

NdFe11TiN

10.0
CoPt
Fe2O3

5.0

MnBi

τ-MnAlSm2Co17
Y2Fe14B

BaFe12O19

0.0

0.5

L10-FeCo
L10-FeNi
Fe16N2Co
FeFePd
Co3Pt

Ni

0.0

FePt

1.0

1.5

Magnetization Js [T]2.0

2.510Discovery of new 1-12-type compounds
Synthesis of single-crystal NdFe12N and(Sm1-αZrα)(Fe1-xCox)12 (0.1≤x≤0.2)
BeyondNd2Fe14BStabilized bulk alloys
Sm0.8Zr0.2(Fe0.8Co0.2)11.5Ti0.5

Sm(Fe1-xCox)12(Sm-Zr)(Fe-Co)12Nd2Fe14B

Films
Sm(Fe0.8Co0.2)11Ti

Y. Hirayama et al. Scr. Mat. 138 (2017) 62
P. Tozman et al. Acta Mat. 153 (2018) 354
P. Tozman et al. Acta Mater. 178 (2019) 114
T. Kuno et al. AIP Adv. 6 (2016) 025221

P. Tozman et al. Acta Mat. 153 (2018) 354
ESICMM

11

Atomic spin model to understand coercivity at T > 0
Stochastic LLG simulation
Spin modelof Nd2Fe14B
82,944 spins

Thermo-statistical analysis (Monte-Carlo)
Spin model of Nd2Fe14B; 713,172 spins (c.a., (21nm)3)

based on ab-initio
parameters

Coercivity (tesla)‐4T; 400K

μ0H0
μ0Hcμ0HK

μ0NDMsNormalized Temperature
S. Miyashita, M. Nishino, et al.
Scr. Mater. 154, 259 (2018)

Coercivity vs. temperature from energy barrier calculations,Y. Toga et al. submitted, presented at MRM2019, E-1-13-009

12

Thermodynamics Data Base13

There was no systematic
database for permanentmagnet alloys.
Compilation of athermodynamic databasefor Nd-Fe-B-Cu-Co-Al-DyGa-O and Sm-Fe-Co-Ti-GaCu-; (on-going)Phase diagram calculation
service since June 2019Abe, in ESICMM Pamphlet 2016

Abe et al. Abstract #157,
JIM2019 Fall,Kou et al. MRM2019 E1-12-P04

Vision : Core center for academia-industry cooperation on
permanent magnets (toward Goal 4)
Our vision is to establish a matching-fund program in NIMS-MOP for cooperation
with industry to inherit the research core and network of ESICMM.
NIMS M-cube Program

Dissemination

Unpublished results, Phase diagrams, etc.

NIMS Permanent Magnet Partnership
14 member companies14

Summary
As the core research center for permanentmagnets, ESICMM has developed:
1. Dy-free Nd-Fe-B comparable to conventional
magnets basing on the new understandings,
2. New Sm(Fe-Co)12-type family of hardmagnetic compounds based on theoreticalpredictions,
3. Fundamental understandings for R&D ofpermanent magnets (thermodynamics andmechanism of coercivity)
4. Future vision for academia-industry
partnership (MOP)

15