Effect of Crystal Structure on the Lightness of Zinc Electroplated Steel Sheet

• KIMOTO Masanari

  Corporate Research & Development Labs., Sumitomo Metal Industries, Ltd.

• YONEMURA Mitsuharu

  Corporate Research & Development Labs., Sumitomo Metal Industries, Ltd.

• YASUDA Hiroyuki

  Graduate School of Engineering, Osaka University

• UMAKOSHI Yukichi

  Graduate School of Engineering, Osaka University

Bibliographic Information

Other Title

• 電気Znめっき鋼板の外観明度に及ぼす電析結晶構造の影響
• デンキ Znメッキ コウハン ノ ガイカン メイド ニ オヨボス デンセキ ケッショウ コウゾウ ノ エイキョウ

Abstract

The lightness of Zn surface electrodeposited with different supporting electrolytes was investigated from the viewpoint of crystal structure and surface morphology using EBSP, AFM and GIXD (Grazing Incidence X-ray Diffraction) techniques. In pulsed current electrolysis containing sodium sulfate for supporting electrolyte, the lightness decreased according to crystal growth of Zn. On the other hand, the lightness remained almost constant in electrolysis containing aluminum sulfate. As for this difference, the usual positive correlation between lightness and preferred orientation of Zn crystal basal plane was not recognized. And GIXD analysis suggested that the crystallographic c axes of Zn electrodeposit using sodium sulfate and aluminum sulfate were roughly oriented perpendicular to the substrate surface, but that there was a small angle deviation inclined in the particular direction to the surface of Zn electrodeposit using sodium sulfate. In contrast, the particular directional deviation was not observed in the surface of Zn electrodeposit using aluminum sulfate. Furthermore, polarization curves of Zn electrodeposition suggested that nuclear generation was enhanced by using aluminum sulfate for supporting electrolyte in comparison with sodium sulfate. From these results, it is presumed that the unregulated crystal growth direction and fast nucleation of Zn crystals with aluminum sulfate caused fine crystal grain. And so, Zn surface possessed excellent smoothness due to its fine crystal facet confirmed by AFM analysis. As a result, it is considered that the lightness is mainly dominated surface smoothness, and that the high lightness of Zn electrodeposit was obtained using aluminum sulfate.

Journal

• Tetsu-to-Hagane

  Tetsu-to-Hagane 92 (9), 551-556, 2006

  The Iron and Steel Institute of Japan

Keywords

• zinc electroplating
• supporting electrolyte
• lightness
• crystal orientation
• grazing incidence X-ray diffraction
• atomic force microscope
• electron backscatter diffraction pattern

Details

• CRID: 1390001205183535232
• NII Article ID: 110004793168
• NII Book ID: AN00151251
• DOI: 10.2355/tetsutohagane1955.92.9_551
• ISSN: 18832954
• ISSN: 00211575
• NDL BIB ID: 8083191
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8083191
• Web Site: https://www.jstage.jst.go.jp/article/tetsutohagane1955/92/9/92_9_551/_pdf
• Data Source:
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  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed