1) The document summarizes research into synthesizing and processing Mn0.4Fe0.3Ga0.3 nanoparticles for potential use in permanent magnets. 2) Through techniques like arc melting, melt spinning, and heat/mechanical treatments, the researchers were able to alter the structure and improve the magnetic properties. 3) Their analysis found that the nanoparticles crystallized in the desirable L12 cubic structure and that the magnetic properties depended on factors like annealing temperature and milling time.

1. Synthesis, processing and characterization of FeMnGa
nanoparticles for permanent magnet applications
G. Sempros1, K. Kanari1, C. Sarafidis1, M. Gjoka2, N. Lupu3, G. Ababei3, D. Niarchos2, O. Kalogirou1
1Dept. of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
2Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, Athens, Greece
3National Institute of R&D for Technical Physics, 47 Mangeron Blvd., 700050 Iasi, Romania
Acknowledgement: This work is partially supported by AUTH Research Committee (Project No 93282 - Support of new
researchers: Advanced Magnetic Materials).
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0
-40
-20
0
20
40
Ms = 47.3 Am
2
/kg
Mr = 9.4 Am
2
/kg (20.00%)
0
Hc = 0.1 T
Mn0.4
Fe0.3
Ga0.3
powder sample
MassMagnetiz.(Am
2
/kg)
Field (T)
Aristotle University of Thessaloniki
Postgraduate Program on Nanosciences & Nanotechnologies (N&N)
Conclusions:
 The L12 structure was observed, in contrast with D019 and L21 which are
usually appearing in Mn3-xGa system.
 Magnetic properties are also depending on the annealing temperature.
 Microstructure is altered after thermal treatment and plays a significant
role in the magnetic properties.
 High Energy Ball Milling reduces magnetization.
SEM – XRD results:
 Homogeneity
 Single phase
 Stoichiometry confirmation
 L12 cubic Cu3Au-type structure
As spun Annealed
Sample Preparation:
Arc melting (Ar), purity >99.99%bulk
Melt spinningnanostructured ribbons
Heat & Mechanical Treatment of
ribbons  Structure tuning & magnetic
properties improvement
Δp = 0,7 mbar
d = 1 mm
Wheel Speed:
20 – 40 m/s
Modern high performance magnets are based in Rare Earth
Intermetallics. Rare Earth minerals are considered strategic
resources due to their low abundance and narrow-located
distribution.
 MnXGa has already been patented as a possible
alternative material for specific applications.
Our Scope
 Improving the magnetic properties of alloys by replacing
a 3d metal with Fe.
 In this study nanostructured Mn0.4Fe0.3Ga0.3 alloys were
prepared and subsequently processed in order to
investigate the effect on their magnetic properties.
 Demand for Rare – Earth free permanent magnets
After 8h of milling After 1h of HEBM
-3 -2 -1 0 1 2 3
-20
-15
-10
-5
0
5
10
15
20
Mn0.4
Fe0.3
Ga0.3
Gal825
8h milling
ribbons
MassMagnetiz.(Am
2
/kg)
Field (T)
-2,0 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 2,0
-12
-10
-8
-6
-4
-2
0
2
4
6
8
10
12
Mn0.4
Fe0.3
Ga0.3
Gal825HE
powder
MassMagnetiz.(Am
2
/kg)
Field (T)
0 100 200 300 400 500 600 700 800 900
0,00
0,02
0,04
0,06
0,08
0,10 cooling
Moment(emu)
Temperature (o
C)
heating