dragica m. minić a ljiljana mihajlović a a.leksandra gavrilović b lidija rafailović b dušan m....
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![Page 1: Dragica M. Minić a Ljiljana Mihajlović a A.Leksandra Gavrilović b Lidija Rafailović b Dušan M. Minić c Corresponding author: Tel +381-11-3336-689; E-mail](https://reader037.vdocument.in/reader037/viewer/2022102900/5515146b550346a87d8b4c46/html5/thumbnails/1.jpg)
Dragica M. Minića
Ljiljana Mihajlovića
A.Leksandra Gavrilovićb Lidija Rafailovićb
Dušan M. Minićc
Corresponding author: Tel +381-11-3336-689; E-mail address: [email protected]
aFaculty of Physical Chemistry, University of Belgrade, Belgrade, Serbia
bECHEM Kompetenzzentrum für Angewandte Elektrochemie GmbH, Wiener Neustadt, Austria
cMilitary Technical Institute, Belgrade, Serbia
References
1. T. Kulik, Journal of Non-Crystalline Solids. 2001, 287, 145.
2. A.A. Soliman, S. Al-Heniti, A. Al-Hajry, M. Al-Assiri, G. Al-Barakati, Thermochim. Acta 2004, 413, 57.
3. D. M. Minić, A. Gavrilović, P. Angerer, D.G. Minić, A. Maričić, Journal of Alloys and Compounds 2009, 476, 705.
4. P. Budrugeac and E. Segal, Rev. Roum. Chim., 2004, 49, 193.
5. L.A. Perez-Maqueda, J.M. Criado, f.
J. Gotor and J. Malék, J. Phy.Chem., 2002, 106, 2862.
Acknowledgements
The investigation was partially supported by the Ministry of Science and Environmental Protection of Serbia, Project 142025.
Kinetics of structural transformations of Fe75Ni2Si8B13C2 amorphous alloy induced
by thermal treatment
Introduction
Metallic glasses are kinetically metastable and thermodynamically unstable materials and undergo transformation to more stable crystal forms at higher
temperatures [1]. The change of structure can lead to change in their technologically important properties, such as the heat capacity, electrical resistivity,
volume and magnetic properties [2]. This imposes the importance of studying thermal properties and kinetics of phase transformations induced by thermal
treatment of amorphous alloys.
The present paper is concerned with the non-isothermal kinetics of multi-step process of structural transformations of Fe75Ni2Si8B13C2 amorphous alloy in
temperature range 293-1273 K by resolution multi-step process to single steps.
Experimental procedures
The ribbon-shaped samples of Fe75Ni2Si8B13C2 amorphous alloy were obtained by standard procedure of rapid quenching of the melt on a rotating disc.
The thermal stability of alloy and the structural transformations has been investigated by the differential scanning calorimetry (DSC) in a nitrogen atmosphere.
Results and discussionThe Fe75Ni2Si8B13C2 amorphous alloy is stable up to 723K when the multi-step of crystallization began giving the overlapping crystallization peaks in the temperature range of 790-860 K [3].
490 500 510 520 530 540 550 560 570 580
0.0
0.2
0.4
0.6
Heat F
low
/ m
W g
-1
Temperature / 0C
a)
490 500 510 520 530 540 550 560 570 580
0.0
0.2
0.4
0.6
Heat F
low
/ m
W g
-1
Temperature / 0C
b)
510 520 530 540 550 560 570 580 590 600 610
0.0
0.4
0.8
1.2
1.6
2.0
Heat F
low
/ m
W g
-1
Temperature / 0C
a)
510 520 530 540 550 560 570 580 590 600 610
0.0
0.4
0.8
1.2
1.6
Heat F
low
/ m
W g
-1
Temperature / 0C
b)
Fig.1 DSC curves at two heating rates: a) as-recorded; b) resolved curves.
5 K min-1
20 K min-1
S
Fig. 2. X-ray diffraction patterns the as-prepared alloy and after thermal treatment at given temperatures.
Fe3Si Fe2B Fe15Si3B2
Annealing Temperature
[K]
Crystallite size
[nm]
Weight fraction
[wt. %]
Crystallite size
[nm]
Weight fraction
[wt. %]
Crystallite size
[nm]
Weight fraction
[wt. %] 780
800
823
923
1023
1123
1273
34 ± 1
34 ± 1
27 ± 3
169 ± 34
153 ± 24
102 ± 15
87 ± 5
70
73
74
78
52
52
46
14 ± 1
10 ± 1
7 ± 2
36 ± 6
52 ± 8
122 ± 13
108 ± 9
9
20
26
22
48
48
54
9 ± 1
13 ± 1
-
-
-
-
-
21
7
-
-
-
-
-
Overall values
Peak 1 Peak 2 Peak 3
Kissinger Ozawa Kissinger Ozawa Kissinger
Ozawa
Ea [kJ mol-1]
ln A
375.1±0.8
56.2±1.0
388.7±0.8
49.1±0.1
341.6±0.5
49.3±0.5
355.4±0.5
43.4±0.5
330±8
47±12
344.7±8
41±12
f f
Fig.3 The application of Perez-Maqueda criterion on the set Avrami-Erofeev equations for all four heating rates.
The detail inspection of our results it was shown the best linearity (R >
0.995) for the set of conversion functions denoted as “An” based on
the Avrami-Erofeev equation in general form where n=3/2, 2, 3, 4,
concerning the process involving the nucleation and nuclei growth. To
confirm the obtained kinetic model IKP method was associated with
the Perez-Maqueda criterion [4-5].
The kinetic triplets for every step were established involving the
conversion function f(α)=3(1-α)[-ln(1-α)]2/3 for all steps and invariant
kinetic parameters Ea = 323 ± 9 kJ mol–1, ln A = 47 ± 1.3 min–1, for first
step; Ea = 304 ± 13 kJ mol–1, ln A = 43.1 ± 1.8 min–1, for the second
step and Ea= 276 ± 20 kJ mol–1, ln A = 38.4 ± 5.0 min–1, for the third
step of crystallization.