computational simulation and testing of nano particle coating in material anti-corrosion
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International Journal of Materials Engineering 2012; 2(2): 11-14
DOI: 10.5923/ij.me.20120303.01
Computational Simulation and Testing of Nano Particle
Coating in Material Anti-Corrosion
Jeremy (Zheng) Li
University of Bridgeport, USA
Abstract The corrosion speed of metal materials varies based on weathering conditions, such as air quality, temperature, moisture, and some other factors of environment. To reduce the corrosion rates, different surface coating technologies have
been applied to improve material anti-corrosion performance. In regular coatings, the adhesive bond is relatively weak that
leads the delamination in coating layer and decrease in coating effective life. This paper studies the mechanism of an-
ti-corrosion in nanocoating process through computational simulation and sample experiment. Both computational modeling
and testing results indicate that the materials with nanocoating are being well protected with longer coated surface life and
more durable anti-corrosion performance if compared to the regular coatings.
Keywords Anti-corrosion, nanotechnology, computational simulation, effective material life, nanocoating
1. Introduction
Products of metal materials are normally subjected to the
corrosion attack in bad weather conditions and corrosion
speed will be increased if metals are exposed to more wet
atmospheric conditions [1]. Under non-wet environmental
condition, the oxide film is developed which can protect
underneath substrate. In wet conditions, such as raining
weather, the corrosion rate of metal products is accelerated
up to the rate of under water products [2]. The wet atmos-
phere can produce the electrolytic droplets with anode in the
centre and ferrous hydroxide is formed to enclose the droplet
which can keep metal products from quick corrosion [3].
Some anti- corrosion surface coatings can decrease the metal
corrosion by sacrificing the coating material elements. In this
case, the coating elements with high electrochemical (cor-
rosive) potential act as the anode to metal materials to further
protect metal products from corrosion [4, 5].
Normally, the molecular bond in conventional surface
coatings are relatively weak and coating life cycle is not very
long in severe weathering condition [6]. The nanocoating
technology has been developed to improve anti-corrosion of
surface coating because of its superior function in an-
ti-corrosion, reliable performance in corrosion resistance,
and non-risk of pollution to environment.
2. Sample Testing
* Corresponding author:
zhengli@bridgeport.edu (Jeremy (Zheng) Li)
Published online at http://journal.sapub.org/ijme
Copyright 2012 Scientific & Academic Publishing. All Rights Reserved
The selected samples have been tested per following
conditions:
. Temperature: 120
. Relative humidity: 92%
. The salt spray
The electrochemical potential is measured by potentiostat
on tested material samples.
Table 1 Experimental results of current density vs. corrosion potential
Potential (V)
Nanocoating
Current Density
(Acm-2)
Conventional Coating
Current Density
(Acm-2)
-1.06 8.08 25.38
-1.04 16.88 45.85
-1.02 28.55 78.82
-1.00 48.35 138.88
-0.98 66.42 215.35
-0.96 92.55 342.88
-0.94 142.38 408.35
-0.92 175.68 512.45
-0.90 185.56 595.38
-0.88 201.36 654.96
Table 2 Experimental corrosion speed vs. percentage of coating film
Percent of
Materials in
Coating Film (%)
Nanocoating
Sample Material
Removal (mg)
Conventional Coating
Sample Material
Removal (mg)
1 20.25 212.38
2 21.35 209.88
3 23.56 205.45
4 26.78 212.55
5 28.38 215.38
6 26.58 217.66
7 25.35 211.55
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Table 1 displays the current density vs. electrochemical
potential in nano and conventional coatings. Since the cur-
rent density in conventional coatings is larger than in nano-
coating, the conventional coatings have lower performance
than nanocoating in anti-corrosion performance. Table 2
indicates the coating material removal vs. percentage of
materials in coating film. It also confirms that the material
removal in conventional coating is larger than in nanocoating
due to superior corrosion-resistant function in nanocoating.
These sample tests show that the nano surface coating has
much better performance than conventional coating in an-
ti-corrosion. The major reason is that the nanocoating can
permeate through the material surface and evolve into sub-
strate material through chemical bonding process. The ex-
periment shows superior and durable anti-corrosion function
in nanocoated materials.
3. Computational Simulation
To compare with prototyped sample testing, the compu-
tational simulation has been performed based on the testing
conditions defined in the section of sample tests.
Fig. 1 shows the weight change of metal sample under
conditions of 120 and 92% RH.
Fig. 1 Electrochemical current density vs. electrochemical potential
Fig. 2 displays the material removal with different percent
of materials in coating film.
Fig. 2 Material removal vs. percent of coating material in coating film
The computer-aided modeling shows the higher an-
ti-corrosion performance in nanocoating due to lower current
density displayed in Fig. 1 and less coated material removal
depicted in Fig. 2. Comparing with conventional coating, the
nanocoating has stronger molecular bond with much less
coating delamination. Both computational simulation and
sample testing show the close results that verifies the credi-
bility and feasibility of this nano coating research and ana-
lytic methodology.
4. Conclusions
This paper studies and analyses the nanocoating on metal
material products through computational simulation and
sample testing. Both results show that the nano coating has
much better surface corrosion-resistant function, superior
anti-rust performance, longer service life cycle, and no risk
of pollution to the environment. Further analysis and testing
will be performed to get more understanding of an-
ti-corrosion mechanism in nanocoating performance.
REFERENCES
[1] Castro, Y., Ferrari, B., Moreno, R. and Duran, A., Coatings produced by electrophoretic deposition from nano-particulate silica sol-gel suspensions, Journal of Surface Coating Technology, 2004, Vol. 182, pp. 199-203.
[2] Gao, W. and Li, Z., Nanostructured alloy and composite coatings for high temperatures applications, Journal of Chemistry, 2004, Vol. 7, pp. 175-182.
[3] Zheludkevich, M., Serra, R., Montemor, M. and Ferreira, M., Nanostructured solgel coatings depod with cerium nitrate as pre-treatments for AA2024-T3 corrosion protection per-formance, Journal of Electrochemistry, 2005, Vol. 5, pp. 208-217.
[4] Sobolov, k. and Gutierrez, M., How nanotechnology can change concrete world, Journal of Ceramic, 2005, Vol. 4, pp.14-17.
[5] Guilemany, J., Dosta, S., Nin, J. and Miguel, J., Study of the properties of WC-Co nanostructured coatings sprayed by high velocity oxy fuel, Journal of Thermal spray Technology, 2005, Vol. 14, pp. 405-413.
[6] Carrado, K., Polymer-clay nanocomposites in G.O. Sho-naike and S.G Advani, Journal of Advanced Polymeric Materials, 2003, pp. 349-348.
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