Influence of electrodeposition parameters on the deposition rate and microhardness of nanocrystalline Ni coatings

✍ Scribed by Jin-Xing Kang; Wen-Zhen Zhao; Gao-Feng Zhang

• Book ID: 104094484
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 670 KB
• Volume: 203
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2009.01.003

✦ Synopsis

In this paper, nanocrystalline nickel (nc-Ni) coatings were prepared by a direct current electrodeposition technique. Their microstructure and microhardness were investigated by a high-resolution transmission electron microscopy and a microhardness tester. It is found that the electrodeposition parameters, including content of C 7 H 4 NO 3 SNa•2H 2 O, temperature and current density, have significant influences on the electrodeposition rate and microhardness of nc-Ni coatings. The electrodeposition rate increases with the current density stepwise. The largest electrodeposition rate is achieved at 60 °C. It decrease when the temperature is larger than 60 °C. The electrodeposition rate decreases with the increased content of C 7 H 4 NO 3 SNa•2H 2 O. The microhardnesses of the nc-Ni coatings are higher on the condition of the larger current density, lower temperature or higher content of C 7 H 4 NO 3 SNa•2H 2 O. But, it remains stable when the current density is in the range of 700-1000 A m -2 . The relationship between the mean grain sizes and microhardness fits for the Hall-Petch function, approximately.