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http://dx.doi.org/10.5695/JKISE.2007.40.1.023

Effect of Al Addition on the Reaction Behavior of Pure Cobalt with Molten Zinc  

Seong, Byeong-Geun (New Metallic Materials Research team, RIST)
Kim, Kyoo-Young (Graduate Institute of Ferrous Technology, POSTECH)
Kwon, Sung-Hee (School of Advanced Materials Engineering, Andong National University)
Lee, Kee-Ahn (School of Advanced Materials Engineering, Andong National University)
Publication Information
Journal of the Korean institute of surface engineering / v.40, no.1, 2007 , pp. 23-31 More about this Journal
Abstract
The objective of this study is to investigate the effect of Al addition on the reaction behavior of cobalt with molten zinc. Pure cobalt specimen was immersion tested in the three kinds of molten zinc (pure, 0.12%Al added and 0.24%Al added) baths at $460^{\circ}C,\;490^{\circ}C\;and\;520^{\circ}C$. For the understanding of degradation processes, specimens were analyzed with scanning electron microscope (SEM) and energy dispersive spectrum (EDS), and electrochemical stripping method. When 0.12% and 0.24% Al was added in molten zinc baths, three intermetallic compounds layers of ${\gamma},\;{\gamma}_1,\;and\;{\gamma}_2$ were formed on the Co matrix and ${\beta}_1$ layer was not formed between the Co matrix and the ${\gamma}$ layer. Particles of CoAl intermetallic compound were formed at the interface between the ${\gamma}_2$ layer and zinc melt and they did not adhere to the Co-Zn intermetallic layer. Weight loss of the Co specimen increased as Al content in the molten zinc increased and the relationship of weight loss vs. immersion time followed parabolic rate law. Rate controlling process for the reaction rate of Co with Al added molten zinc was analyzed as the diffusion process of Al atom through a boundary layer between the ${\gamma}_2$ layer and the Al added zinc melt.
Keywords
Co-binder; Al added molten Zinc; Parabolic rate law; CoAl particle; Diffusion process of Al atom; Boundary layer;
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  • Reference
1 H. Nakahira, Y. Harada, T. Doi, Y. Takatani, T. Tomita, J. High Temp. Soc., 16 (1990) 317
2 D. Horstmann, F. Peters, Proc. 9th Inter. Conf. on H.D.G., London, ZDA, (1971) 75
3 H. Koga, Y. Uchiyama, T. Aki, J. Jpn. Inst. Met., 42 (1978) 136   DOI
4 K. Tani, T. Tomita, Y. Kobayashi, Y. Takatani, Y. Harada, ISIJ International, 34 (1994) 822   DOI   ScienceOn
5 B. G. Seong, S. Y. Hwang, M. C. Kim, K. Y. Kim, J. Kor. Inst. Met. & Mater., 38 (2000) 488
6 X. G. Zhang, I. C. Bravo, Corrosion, 50 (1994) 308   DOI   ScienceOn
7 P. Villars, A. Prince, H. Okamoto, Handbook of Ternary Alloy Phase Diagram, ASM International, 3 (1995) 2098
8 P. F. Tortorelli, ASM Handbook, Corrosion, 13 (1987)
9 J. M. Mataigne, P. Drillet, J. M. Prat, D. Mareuse, P. Terreaux, M. Guttmann, Proc. Galvatech '95 Conf., (1995) 589
10 H. Nakahira, Y. Harada, K. Tani, Proc. ATTAC'88, Osaka, (1988) 73
11 T. Tomita, Y. Takatani, Y. Kobayashi, Y. Harada, H. Nakahira, ISIJ International, 33 (1993) 982   DOI   ScienceOn
12 M. Nakagawa, J. Sakai, T. Ohgouchi, H. Ohkoshi, Tetsu to Hagane, 81 (1995) 989   DOI
13 M. Sawa, J. Oohori, Processing of International Thermal Spray Conference '95, Kobe, Japan, (1995) 37
14 B. G. Seong, S. Y. Hwang, M. C. Kim, K. Y. Kim, Surface and Coatings Technology, 138 (2001) 101   DOI   ScienceOn
15 D. Horstmann, Proc. 6th Inter. Conf. on H.D.G, London, ZDA, (1962) 319
16 B. G. Seong, K. Y. Kim, K. A. Lee, J. Kor. Inst. Met. & Mater., Submitted