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Electrophoretic deposition of thin
alumina films from water suspension
K. Simovic, V.B. Miskovic-Stankovic*, D. Kicevic , P. Jovanic
Physicochemical and Engineering Aspects 209 (2002) 47–55
Advisor : Prof. S.C.Wang
Advisee : Jyun-Jia Huang
2010/01/07
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outline
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Introduction
Experimental
Results and discussion
Conclusions
Future work
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Introduction
• 近年來，電泳沉積常被使用在複合層、薄層、絲、有機陶瓷和生物陶
瓷上。
• 在這篇報告中，主要是製備出最佳的氧化鋁水懸浮液參數，獲取孔隙
率最低的薄膜
( zeta 電位、低黏度、施加電壓、沉積時間 and 懸浮液濃度)
• Zeta電位、 黏度計、OM and SEM.
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Experimental
Dolapix
ET 85
1.4 wt.%
分散劑
alumina
A16SG
10、20、30
wt.%
DI water
polyvinyl
alcohol
1.0 wt.%
凝聚劑
pH 4 by 65% nitric acid
ball mill for 2 h
without balls for 1 h
EPD
dried at room temperature
SEM
OM
EPD 參數
D.C = 30 - 250 V
cathode ： steel (5X5 mm)， anode
Pt
distance： 18 mm
deposition time = 2、5、10 min
δ＝G(ρS)-1
δ：thickness of alumina films
G ：w2-w1
ρ：3.96 g cm-3 (powder density)
S ： surface area of the steel
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：
Results and discussion
Table 1
The values of zeta potential, ξ, of alumina suspension ( treated and untreated in the ultrasonic bath) for
different type of deflocculant
分散劑
ξ (mV)
Treated suspension Untreated suspension
Dolapix PC 33
66.8
60.6
Dolapix ET 85
78.8
77.5
•X-ray diffraction pattern of alumina
poweder AlcoaA-16 SG
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•The viscosity of the alumina suspension
versus deflocculant content.
1.2 1.4 1.6
Table 2
The values of zeta potential, ξ, of alumina suspension for different content of deflocculant
Dolapix ET 85
過多的分散劑會破壞懸浮液的穩定性
分散劑濃度(wt.%)
ξ (mV)
1.2
54.6
1.4
77.5
1.6
79.8
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Alumina film thickness as a function of applied deposition voltage
(range 50-250 V) for concentration of:
(a) 10 wt.%, (b) 20 wt.% and (c) 30 wt.% alumina suspension,
and different deposition time.
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Alumina film thicknes as a function of applied deposition
voltage (range 30-90 V) for concentration of:
(a) 10 wt.%, (b) 20 wt.% and (c) 30 wt.% alumina suspension,
and different deposition time.

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•The percentage of alumina film surface
covered by pores versus applied deposition
voltage for different content of alumina powder
in suspension (deposition time: 10 min).
30V
The pore number vs. applied deposition voltage in the range of:
(a) 30-90 V and (b) 50-250 V, for 20 wt.%
alumina suspension and different deposition time.

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The percentage of alumina film surface covered by
pores vs. applied deposition voltage in the of:
(a) 30-90 V and (b) 50-250 V, for 20 wt.% alumina suspension
and different time.
Dependence of mean pore diameter on aplied deposition
voltage in the range of:
(a) 30-90 V and (b) 50-250 V, for 20 wt.% alumina suspension
and different deposition time
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Fig. 9. The microphotographs of alumina film surface electrodeposited
from 20 wt.% alumina suspension at 30 V and for deposition time of 10 min:
(a) optical microscope view and (b) scanning electron microscope view.
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Conclusions
• 為了在不繡鋼上沉積氧化鋁薄膜，氧化鋁水懸浮液必須
要高zeta 電位和低黏度。
• 最佳的氧化鋁薄膜參數為施加電壓:30V、懸浮液濃度
為20wt.%和沉積時間10min。
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THANK YOU !!
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