Optimization of Process Parameters to Obtain Quality Amorphous Ribbons
for ultra soft magnetic applications
M Shanthi Raju1, Bhaskar Majumdar2, D Arvindha Babu2, M K Mondal1
1
2
National Institute of Technology, Durgapur. India,
Advanced Magnetic Group, DMRL Hyderabad-500058
Shantimr@gmail.com, Tel.: +91-9059461351
Keywords: Planar flow melts spinning (PFMS) Taguchi
method, ANOVA method
Introduction: Fe73.5 Si13.5 B9 Nb3 Cu1 alloys [1] in the form
ribbon exhibits superior soft magnetic prosperities due to
presence of partially devitrified nanocrystalline phase in the
amorphous matrix. They are used in the form of wide, thin and
continues amorphous ribbons which produced by Planar Flow
Melts Spinning (PFMS) process. The process parameters
control the formation of quality ribbon are wheel speed V,
pressure P, Nozzle wheel gap G and Temperature T. The
present investigation deals with the process parameter of
PFMS using Taguchi method for obtaining optimum
thickness, surface roughness.
Experimental & Procedure: All experiments have been
carried out using Taguchi method with L16 orthogonal array
with four control factors (process parameters) and four levels.
Table.1 shows the L16 orthogonal array consisting of 16 no.’s
of experiments with four control factors and four levels. The
surface roughness (SR) of all ribbons was measured using
Talysurf instrument. The thickness (t) and structure of all
ribbons were evaluated using screw gauge and X- Ray
diffractometer system.
Results and Discussion:
The thickness and surface roughness values obtained all
experiments are given against each experiment. Figure 1
shows the main effect of parameter on thickness, values of all
16 experiments plotted at different levels. The optimized
parameters obtained from figure are A4B3C3D2. Finally a
confirmation experiment has been carried out and obtained an
amorphous ribbon with very low thickness with high quality
lengthy ribbon. ANOVA method has been applied to obtain
the percentage contribution of each control parameter and
found that temperature contributes high with 54.25% followed
by wheel speed with 10.75% The Nozzle wheel gap
contributes 2.49% and the pressure contributes the least with
0.53 %.
S.N0.
P
(kpa)
(B)
6.9
G
(mm)
(C)
0.25
T (k)
(D)
(t)
µm
S.R
L1
V
(m/s)
(A)
15
1373
85.20
1.64
L2
L3
L4
L5
L6
L7
L8
L9
L10
L11
L12
L13
L14
L15
L16
15
15
15
20
20
20
20
25
25
25
25
30
30
30
30
13.8
20.7
27.6
6.9
13.8
20.7
27.6
6.9
13.8
20.7
27.6
6.9
13.8
20.7
27.6
0.3
0.35
0.4
0.3
0.25
0.4
0.35
0.35
0.4
0.25
0.3
0.4
0.35
0.3
0.25
1423
1473
1523
1473
1523
1373
1423
1523
1473
1423
1373
1423
1373
1523
1473
85.54
45.33
35.53
66.08
39.42
40.46
56.47
49.27
81.05
49.16
37.28
72.76
57.97
60.15
54.34
1.94
0.95
1.77
1.49
0.89
1.31
1.21
1.62
1.54
1.81
1.52
1.21
1.21
1.69
2.12
Table.1 L16 orthogonal array consisting of 16 experiments
based on 4 control factors with 4 levels and thickness and
surface roughness values obtained in all experiments.
80
Wheel Speed
Pressure
Nozzle Wheel Gap
Tempareture
75
70
Thickness(m)
Abstract: Process parameters for producing thin, wide and
continues amorphous ribbons (Fe73.5 Si13.5 B9 Nb3 Cu1) have
been optimized by adopting Taguchi method. A L16
orthogonal array consisting of 16 experiments has been used
in this study to find out the optimum thickness for obtaining
amorphous ribbons. Surface roughness of all ribbons has also
been evaluated. The percentage contribution of control
parameters which influences the thickness of the ribbon has
been obtained statistically using analysis of variation
(ANOVA) method.
65
60
55
50
45
40
1
2
3
4
Level
Figure.1 The main effect of parameter on thickness, values of
all 16 experiments plotted at different levels
Conclusion:
PFMS process parameters have been optimized using taguchi
method to obtain quality amorphous ribbons with low
thickness have been optimized. The percentage contribution of
each parameter affecting the PFMS process have been
obtained using ANOVA method.
Acknowledgement:
We would like to thank Director, DMRL for the permission to
carry out this research work in DMRL.
Reference:
[1]Yosizawa et. al. J. Mag. Mag. Mater. 62 (1986) 143
[2] B. Majumdar • M. Sowjanya • M. Srinivas •D. A. Babu T.
Kishen K. Reddy (2012)