Journal of the Korea Convergence Society (한국융합학회논문지)

Korea Convergence Society (한국융합학회)
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Effect of current density, temperature and electrolyte concentration on Composition of Zn-Ni Electrodeposits

Zn-Ni도금의 합금화에 미치는 전류밀도, 온도와 전해액농도의 영향

  • Kang, Soo Young (Dept. of Metallurgical & Material Engineering, lnha Technical College)
  • 강수영 (인하공업전문대학교 금속재료과)
  • Received : 2017.10.10
  • Accepted : 2017.11.20
  • Published : 2017.11.28
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Abstract

In the industry, galvanizing using the principle of sacrificial anode is used Zn-Ni alloy plating was developed as one of the measures to increase the corrosion resistance rather than pure zinc plating. The alloy plating layer has a corrosion resistance of 4-5 times that of the pure zinc plating layer, so that it is applied to automotive parts requiring high corrosion resistance even though the plating cost is high. The amount of Zn-Ni alloy plating solution is a sulfuric acid bath, a chlorinated bath, an alkali bath, and an ammonia bath. Here, the influence of the electrolytic conditions on the composition of the alloy plating in the chloride bath was investigated. The results are explained by the cathode overvoltage and the diffusion coefficient. In general, as the overvoltage of the cathode increases, the concentration polarization becomes more important than the activation polarization. The concentration polarization is determined by element diffusion in the diffusion layer. That is, as the overvoltage of the cathode increases, the Zn content having a large diffusion coefficient increases.

산업계에서는 희생양극의 원리를 이용한 아연도금이 사용되고 있다. 순수아연도금보다 내식성을 증가시키기 위한 방안의 하나로 Zn-Ni 합금도금이 개발되었다. 합금 도금층은 순 아연 도금층에 비하여 4-5배의 내식성을 가지고 있어서 도금 단가가 높음에도 불구하고 고내식성을 요구하는 자동차 부품 등에 적용이 증가되고 있다. Zn-Ni 합금도금액은 황산욕, 염화욕, 알칼리욕과 암모니아욕 등이 사용되고 있다. 여기에서는 염화욕에서 합금도금의 조성에 미치는 전해조건의 영향을 조사하였다. 그 결과는 음극 과전압 및 확산계수에 의해 설명하였다. 일반적으로 음극의 과전압이 증가함에 따라 활성화분극보다 농도분극이 중요하게 된다. 농도분극은 확산 층 내의 원소 확산에 의해 결정된다. 즉 음극의 과전압이 증가함에 따라 확산계수가 큰 Zn 함량이 증가한다.

Keywords

References

  1. R. Fratesi, G. Roventi, "Corrosion resistance of Zn-Ni alloy coatings in industrial production, Surface and Coatings Technology", Vol. 82, pp.158-164, 1996 https://doi.org/10.1016/0257-8972(95)02668-1
  2. T. V. Byk, T. V. Gaevskaya, L. S. Tsybulskaya, "Effect of electrodeposition conditions on the composition, microstructure, and corrosion resistance of Zn-Ni alloy coatings", Surface & Coatings Technology, Vol. 202, pp. 5817-5823, 2008. https://doi.org/10.1016/j.surfcoat.2008.05.058
  3. J. B. BAJAT, M. D. MAKSIMOVIC, V. B. MISKOVIC-STANKOVIC and S. ZEC, Electrodeposition and characterization of Zn-Ni alloys as sublayers for epoxy coating deposition, Journal of Applied Electrochemistry", Vol. 31, pp. 355-361, 2001. https://doi.org/10.1023/A:1017580019551
  4. Tatsuo Ishikawa, Kumi Matsumoto, Akemi Yasukawa, Kazuhiko Kandori, Takenori Nakayama, Takayuki Tsubota, M.A.J. Somers, "Influence of metal ions on the formation of artificial zinc rusts", Corrosion Science, Vol. 46, pp. 329-342, 2004. https://doi.org/10.1016/S0010-938X(03)00155-0
  5. G. ROVENTI, R. FRATESI, R. A. DELLA GUARDIA and G. BARUCCA, "Normal and anomalous codeposition of $Zn{\pm}Ni$ alloys from chloride bath", Vol. 30, pp. 173-179, 2000. https://doi.org/10.1023/A:1003820423207
  6. R. Ramanauskas. L. Gudavic iute, A. Kalinicenko, R. Juskenas, "Pulse plating effect on microstructrue and corrosion properties of Zn-Ni alloy coatings", J Solid State Electrochem, Vol. 9, pp. 900-908, 2005. https://doi.org/10.1007/s10008-005-0049-z
  7. J. Giridhar and W. J. van Ooij, "Study of Zn-Ni and Zn-Co alloy coatings electrodeposited onsteel strips II: Corrosion, dezincification and sulfidation of the alloy coatings. Surface and Coatings Technology", Vol. 53, pp. 35-47, 1992. https://doi.org/10.1016/0257-8972(92)90101-F
  8. H. Ashassi-Sorkhabia, A. Hagraha, N. Parvini-Ahmadib, J. Manzooric, "Zinc nickel alloy coatings electrodeposited from a chloridebath using direct and pulse current", Surface and Coatings Technology, Vol. 140, pp. 278-283, 2001. https://doi.org/10.1016/S0257-8972(01)01032-5
  9. P S Salmoni W S Howellsi and R Mills, "The dynamics of water molecules in ionic solution: 11. Quasi-elastic neutron scattering and tracer diffusion studies of the proton and ion dynamics in concentrated Ni2+, Cu2+ and Nd3+ aqueous solutions", J. Phys. C: Solid State Phys., Vol. 20, pp. 5727-5747, 1987. https://doi.org/10.1088/0022-3719/20/34/011
  10. S. F. Patil, A. V. Borhade and Munmun Nath, "Diffusivity of Some Zinc and Cobalt Salts in Water", J. Chem. Eng. Data, Vol. 38, pp. 574-576, 1993. https://doi.org/10.1021/je00012a025
  11. Ravindran Visalakshi & Muralidharan V S., "Dissolution of Zn-Ni alloy deposited on foreign substrates", Indian J Chem Technol., Vol. 3, pp. 231-235, 1996.
  12. Ravindran Visalakshi.Krishnan R M. Muralidharan V S., "Corrosion resistant Zn-Ni alloy deposit.", Truns Inst Metal Fin Assoc (India), Vol. 43, pp. 189-199, 1995.
  13. Rajagopalan S. R., "Electrodeposition of Ni-Zn alloys", Metalfinishing, Vol. 70, pp. 52-57, 1972.
  14. Ravindran Visalakshi & Muralidharan V S., "Anomalous codeposition of Zn-Ni alloy from sulphamate bath.", J. Chem. Technol., Vol. 2, pp. 330-334, 1995.
  15. Horkans Jean, "on the role of buffers and anions in NiFe Electrodeposition", J. Electrochem. Soc, Vol. 126, pp. 1861-1867, 1979. https://doi.org/10.1149/1.2128816
  16. Horkans Jean, "Effect of plating parameters on electrodeposited Ni-Fe", J. Electrochem. Soc., Vol. 128, pp. 45-50, 1981. https://doi.org/10.1149/1.2127385