Current Efficiency and Composit ion of Zn-Cr and Zn-Cr-X Ternary Alloy Electrodeposits

고속도금된 Zn-Cr 및 Zn-Cr-X 3원합금의 전류효율 및 조성

  • Ye G.C. (College of Metallurgical Engineering and Material Science, Yeungnam Unvi.) ;
  • Kim D.Y. (College of Metallurgical Engineering and Material Science, Yeungnam Unvi.) ;
  • Ahn D.S. (Dongbu Steel. Technical Research Lab.)
  • 예길촌 (영남대학교 재료금속공학부) ;
  • 김대영 (영남대학교 재료금속공학부) ;
  • 안덕수 (동부제강 기술연구소)
  • Published : 2003.06.01

Abstract

The current efficiency and the composition of Zn-Cr and Zn-Cr-X (X : Co, Mn) alloy electrodeposits were investigated by using chloride bath with EDTA auditive and flow cell plating system. The current efficiency of Zn-Cr alloy decreased with increasing current density, while it increased with the content of Co and Mn of the Zn-Cr-X alloy bath in high current density region. The Cr content in Zn-Cr alloy increased from 1.4-2.7 to $28wt\%$ with increasing current density and the phase structure of the alloys changed from $\eta-Zn$ through $\eta-Zn+\gamma'-ZnCr\;to\;\gamma'-ZnCr$ with Increasing Cr content of the alloys. The Co content in Zn-Cr-Co alloys increased with Co content of the bath, while Cr content of the alloy increased or decreased in low current density region $(10-75A/dm^2)$ or high current density region $(75-100A/dm^2)$, respectively. $\gamma-ZnCo$ phase was formed in the Zn-Cr-Co alloy with above $9.0wt\%$ Co. The content of Mn and Cr in Zn-Cr-Mn alloys increased or decreased with the increase of current density in high current density region, respectively while Cr content of the alloy decreased noticeably with the increase of Mn content in the bath. Two phases of $\delta_1-ZnMn$ and $\gamma'-ZnCr$ were formed in the Zn-Cr-Mn alloy with above $8.6wt\%$ Mn.

Keywords

References

  1. T, Kanamura, S. Suzuki, K. Arai, GALVANOTE-CH. '92, sept. 8-10, Verlag Stahleisen, Dusse-Idorf, (1992) 331
  2. S. Suzuki, A. Fukuda, CAMP-ISIJ, 4 (1991)1601-1602
  3. Kanamura et al., U.S PAT., 4,897,317, Jan. 30(1990)
  4. Urakawa et al., U.S PAT., 5,458,764, Oct. 17(1995)
  5. Otajima, et al., JP4-304387, Oct. 27 (1992)
  6. D.S.Ahn, POSCO reseach Rep. (1995, 2000)
  7. Otajima, et al., JP4-314885, Nov. 6 (1992)
  8. T.Akiyama, H.Fukushima, T.Urakawa, J. Surf.Finish. Soc. Japan. 42 (1991) 1039 https://doi.org/10.4139/sfj.42.1039
  9. A.Watson, Y.J.Su, C.U.Chisholm, Trans. Inst.Metal Finish, 71 (1) (1993) 15 https://doi.org/10.1080/00202967.1993.11870976
  10. D.S.Ahn, D.Y.Kim, G.C.Ye, J. Kor. Inst. Surf Eng. 35 (4) (2002) 232
  11. H.Fukushima, T.Akiyama, K.Kiyotami, Shigen-to-Sozai, 109 (1993) 861 https://doi.org/10.2473/shigentosozai.109.861
  12. Y.Lim, T.Ohgai, J. of Surf.Finish. Soc.Japan, 47(10) (1996) 868 https://doi.org/10.4139/sfj.47.868
  13. H.Fukushima et al., ibid, 33 (11) (1982) 574
  14. D.S.Ahn, Ph.D. Thesis, Electrodeposition Mech-anism and Characterlstics of Zn and Zn-CrAlloy, (2002) 12, Yeungnam Univ.
  15. S.Hashimoto, S.Ando, M.Sagiyama, J. JapanInst.met., 62 (1) (1998) 9
  16. M.Hino, H.Kawasaki et al., J. of Surf. FinishSoc. Japan, 43 (1992) 873 https://doi.org/10.4139/sfj.43.873
  17. R.Salas, R.Ichino, M.Okido Abstract No88 (1999)
  18. N.Boschkov, et al., Metalloberflaeche, 52 (7) (1998) 514
  19. M.Eyraud, J.Crousier, Metal Finishing, (2001)56