원심분무법 제조 Fe-Ni-Mo계 분말을 사용한 소결코아의 제조

목차

INTRODUCTION

EXPERIMENTAL

RESULTS AND DISCUSSION
A. Plasma Electrode Rotating Centrifugal Atomization

B. AC Magnetic Properties of Sintered Cores

REFERENCE

FIGURE CAPTION

본문내용

of Powder Metallurgy & Powder
Technology, 16, 359(1980).
7. M.Kersten, Z. Angew. Phys. 7, 313(1956).
8. S. Chikazumi, Physics of Ferromagnetism, Vol.2, p.248, Syokabo Books, Tokyo,
(1990).
9. K. Ohota, Principle of Magnetic Engineering, 3rd Ed., p.291, Kyoritsu Publishing Co., Tokyo, (1985).
10. S.Chikazumi, K.Adachi and Y.Ishikawa, Magnetic Materials Handbook, p.1086,
Asakura Publishing Co., Tokyo, (1982).
11. Japan Patent 62-103343
FIGURE CAPTION
Fig. 1 Variation of productive capacity of centrifugal
atomization as a function of (a) input ampere,
and (b) rotational speed of ingot.
Fig. 2 SEM and optical micrographs of centrifugal atomized
powders at (a) surface, and (b) cross section
Fig. 3 Particle size dependency of magnetic properties
and density of Fe-79Ni-4Mo cores as a
function of sintering time.
Fig. 4 Bm dependency of magnetic properties of
Fe-79Ni-4Mo cores as a function of particle size
Fig. 5 Optical micrographs of sintered Fe-79Ni-4Mo
cores different paticle size of (a) 53∼90 μm,
and (b) 125∼180 μm.
Fig. 6 Variation of magnetic properties and density
of Fe-79Ni-4Mo cores mixed with two
different particle size of powders.
Table Ⅰ Effect of plasma current on the particle size produced
at a rotating speed of 27.5 m/sec
applied
current
(A)
particle size distribution (%)
(rotational speed of ingot : 27.5 m/sec)
∼53μm
53∼90μm
90∼125μm
125∼180μm
180∼250μm
550
0.53
6.52
24.94
46.02
21.99
750
0.29
7.43
28.51
37.09
26.68
850
0.29
8.10
39.51
33.15
18.95
950
0.62
7.37
37.05
28.05
26.47
1050
0.53
6.81
31.50
35.29
17.87
Table Ⅱ Effect of rotating speed on the particle size produced
with a plasma current of 850 A
rotational speed
(m/sec)
Particle size distribution (%)
(applied current : 850 A)
∼53μm
53∼90μm
90∼125μm
125∼180μm
180∼250μm
23.5
0.21
2.33
22.22
36.47
38.77
27.5
0.29
8.10
39.51
33.15
18.95
33.4
2.36
27.62
39.54
24.18
6.31
Table Ⅲ Comparison of DC magnetic properties obtained from
the present work and previous work for the sintered
Fe-79Ni-4Mo cores
composition
particle size (μm)
B10 (G)
Hc (Oe)
μmax
ρ
(g/cm3)
Fe-79Ni-4Mo
present
work
125∼180
6850
0.085
40000
8.24
180∼250
6700
0.08
38000
8.20
previous work
7000
0.085
35000
7.9

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원심분무법,   소결코아의 제조