**5. Acknowledgements**

The author would like to thank the financial support of this research from the National Science Council of the Republic of China, Taiwan (NSC96-2221-E007-066-MY3). Mr. Yih-Farn Kao is grateful for his help in compilation of this manuscript. This work is mainly from the 2009 master thesis of the Department of Materials Science Engineering of the National Tsing Hua University by Mr. Tsung-Dar Lee, who was guided by the author.

#### **6. References**


In C-0.50 and C-1.00, the secondary passivation phenomenon in polarization curve results

pre-exponential factor A and activation energy Ea increase with Al content. However, A

Al is an inferior factor to the passive corrosive resistance but helpful for the general corrosive resistance for AlxCoCrFeNi in H2SO4. The thickness and the density of oxide layers promoted by the addition of Al compete with each other at various temperatures. At ambient temperature, the thick oxide layer dominates Icorr value; at temperatures higher

The author would like to thank the financial support of this research from the National Science Council of the Republic of China, Taiwan (NSC96-2221-E007-066-MY3). Mr. Yih-Farn Kao is grateful for his help in compilation of this manuscript. This work is mainly from the 2009 master thesis of the Department of Materials Science Engineering of the National

[1] See for example, D.R. Gaskell, Introduction to the Thermodynamics of Materials, 3rd ed.,

[2] K.H. Huang, Multicomponent alloy systems containing equal-mole elements, M.S. thesis, Department of Materials Science and Engineering, NTHU, Taiwan, 1996. [3] K.T. Lai., Microstructure and properties of multicomponent alloy system with equal-

[4] Y.F. Kao, S.K. Chen, J.H. Sheu, J.T. Lin, W.E. Lin, J.W. Yeh, S.J. Lin, T.H. Liou,

[6] P.K. Huang, J.W. Yeh, T.T. Shun, S.K. Chen, Multi-principal-element alloys with

[7] C.Y. Hsu, J.W. Yeh, S.K. Chen, T.T. Shun, Wear resistance and high-temperature

CoFeMnTixVyZrz alloys, Int. J. Hydrogen Energy 35 (2010) 9046-9059. [5] J.W. Yeh, S.K. Chen, S.J. Lin, J.Y. Gan, T.S. Chin, T.T. Shun, C.H. Tsau, S.Y. Chang,

design concepts and outcomes, Adv. Eng. Mater. 6 (2004) 299-303.

mole elements, M.S. thesis, Department of Materials Science and Engineering,

C.W. Wang, Hydrogen storage properties of multi-principal-component

Nanostructured high-entropy alloys with multiple principal elements: Novel alloy

improved oxidation and wear resistance for thermal spray coating, Adv. Eng.

compression strength of FCC CuCoNiCrAl0.5Fe alloy with boron addition, Metall.

Tsing Hua University by Mr. Tsung-Dar Lee, who was guided by the author.

Taylor & Francis, Washington D.C., 1995, p. 204.

C, the loss oxide layer does. Intuitionally, one may improve the corrosion

affects Icorr more significantly than it does so for Ea at higher temperatures (> 27

C).

C). That more closely examining Arrhenius plots of Icorr reveals that both

C), while Icorr decreases with x

C) and,

from selective dissolution of the Al and Ni-rich phase.

performance for AlxCoCrFeNi by adjusting Al content.

conversely, at lower temperatures (< 23

NTHU, Taiwan, 1998.

Mater. 6 (2004) 74-78.

Mater. Trans. A 35A (2004) 1465-1469.

at lower ones (< 23

**5. Acknowledgements** 

**6. References** 

than 27

Moreover, Icorr increases with x at higher temperatures (> 27


**7** 

*La Plata Argentina* 

**Reinforcement Fibers** 

*UTN (Universidad Tecnológica Nacional),* 

Carlos Alberto Giudice

**in Zinc-Rich Nano Lithiun** 

**Silicate Anticorrosive Coatings** 

*CIDEPINT (Centro de Investigación y Desarrollo en Tecnología de Pinturas),*

Well-known the electrochemical nature of most processes of corrosion, the technology of anticorrosive coatings is oriented in the direction of making products that control the development of electrode reactions and that generate the isolating of metal surface by

The zinc-rich coatings and those modified with extenders and/or metal corrosion inhibitors display higher efficiency than other coatings. A problem that presents this type of primers is the extremely reactive characteristic of metallic zinc; consequently, the manufacturers formulate these coatings in two packages, which imply that the zinc must be incorporated to the vehicle in previous form to coating application (Jianjun et al., 2008 & Lei-lei & De-liang,

Considering the concept of sacrificial anode (cathodic protection), coatings that consist of high purity zinc dust dispersed in organic and inorganic vehicles have been designed; in these materials, when applied in film form, there are close contacts of the particles among

The anodic reaction corresponds to the oxidation of zinc particles (loss of electrons) while the cathodic one usually involves oxygen reduction (gain of electrons) on the surface of iron or steel; the "pressure" of electrons released by zinc prevents or controls the oxidation of the metal substrate. Theoretically, the protective mechanism is similar to a continuous layer of zinc applied by galvanizing with some differences because the coating film initially presents

In immersion conditions, the time of protection depends on the zinc content in the film and on its dissolution rate. The mechanism is different for films exposed to the atmosphere, because after the cathodic protection in the first stage, the action is restricted substantially to a barrier effect (inhibition resistance) generated by the soluble zinc salts from corrosion by sealing the pores controlling access to water, water vapor and various pollutants. Due to the

themselves and with the base or metallic substrate to be protected.

in general a considerable porosity (Jegannathan et al., 2006).

applying films with very low permeability and high adhesion (Sorensen et al., 2011).

**1. Introduction** 

2010).

