Acta Metallurgica Sinica (金属学报) 2013/49:12 PP.1617-1622
Nanosized multilayered Ni coatings were deposited on Q235 steel substrates by ultrasound-assisted electrodeposition. The multilayered Ni coating has a laminated structure of or-dinary Ni layer/ultrasonic Ni layer. In order to determine the corrosion and wear property of this novel multilayered Ni coating, conventional Ni coating and bilayered Ni coating were prepared. The phase structure and average grain size of the Ni coatings were determined by X-ray diffraction analysis. Cross section morphologies were observed by scanning electron microscope. Corrosion properties of the Ni coatings were investigated by the immersion test in 7% HCl solution at room temperature, and then their corrosion morphologies were examined by scanning electron microscope. Another way to evaluate the corrosion resistance of the Ni coatings is to calculate the porosity of the Ni coat- ings using porosity analysis software on an optical microscope. Wear resistance of the Ni coatings were evaluated by rubber wheel test method. The test condition was 400# SiC emery paper and the applied load on the samples is 6.3 N. Moreover, after 1500 cycles, cross sections of the worn Ni coating samples along the wear direction were observed by means of scanning electron microscope. The results indicate that the growth orientation of the multilayered Ni coating is (111) preferably. Its microstructure is obviously a smooth stacker-up laminated structure. Hence, the epitaxial colum- nar growth of the conventional Ni coating is annihilated by the formation of the multilayered struc- ture. Compared with the conventional Ni coating, not only the wear resistance of the multilayered Ni coating is improved obviously, but also the corrosion resistance of the multilayered Ni coating is enhanced dramatically. With multilayered structure, the pinholes were obviously inhibited. That is because the multilayered Ni coating can cover the whole surface of the substrate without pinhole in- terruption. The multilayered structure can extend the pinhole passages extremely for the multilayered Ni coating, unlike the direct and straight pinhole passages for the conventional Ni coating. Therefore, its corrosion mechanism is the uniform corrosion, instead of the by drogen blistering and Fe/Ni galvanic couples for the ordinary Ni coating. The wear mechanism of the multilayered Ni coating is the adhesive wear, which is a kind of the so-called micro-area detachment; while that of the ordinary Ni coating consists of adhesive wear, which can lead to the wear behavior of the bulk damage due to the columnar microstructure.
 Chen Y. Practical Electrodeposition Technology. Beijing:National Defence Industrial Press, 2003:147(陈亚.现代实用电被技术.北京:国防工业出版社,2003:147)
[l6] Wang Y, Deng Y Z, Ma Y T, Gao F. Surf Coat Techraol, 2011:206:1203.
 Iwasaki H, Higashi K, Nieh T G. Scr Mater, 2004:50:395.
 Chen L, Wang L P, Zeng Z X, Zhang J Y. Mater Sci Eng,2006:A434:319.
 Hamid Z A, Ghayad I M. Mater Lett, 2002:53:238.
 Erb U. Nanostruct Mater, 1995:6:533.
 Aruna S T, William G V K, Rajam K S. J Alloys Compd,2009:468:546.
 He Y L. Electroplating Finish, 2002:21(2):1(何跃林·电铰与涂饰,2002:21(2):1)
 Cheung C, Djuanda F, Erb U, Palumbo G. Nanostruct Mater, 1995:5:513.
 Cheng D, Yan Z J, Yan L. Acta Metall Sin, 2008:44:1461(程东,严志军,严立.金属学报,2008:44:1461)
 Tayyebi M, Eghbali B. Mater Sci Eng, 2013:A559:759.
 Menezes S, Anderson D P W. J Electrochem Soc, 1990:137:440.
 Rao S I, Hazzledine P M. Philos Mag, 2000:80A:2011.
 Rajasekaran N, Mohan S. Corms Sci, 2009:51:2139.
 Haseeb A S M A, Celis J P, Roos J R. J Electrochem Soc,1994:141:230.
 Troyon M, Wang L. Appl Surf Sci, 1996:103:517.
 Xie T T, Mao S D, Yu C, Wang S J, Song Z L. Vacuum,2012:86:1583.
 Xia F F, Wu M H, Wang F, Jia Z Y, Wang A L. Curr Appl Phys, 2009:9(1):44.
 Zhu Y K, Yu Z M, Niu Y S, Ding W J. J Adhesion Sci Technol, 2012:26:1645
 Xia F F, Liu C, Wang F, Wu M H, Wang J D, Fli H L,Wang J X. J Alloys Co}npd, 2010:490:431.
 Jensen J A D, Pocwiardowski P, Persaon P O A, Hultman L, Mv}ller P. Cherrephys Lett, 2003:368:732
 Lorimer J P, Pollet B, Phull S S, Mason T J, Walton D J,Geissler U. Electrochi}n Acta, 1996:41:2737.
 Liu P S, Liang K M. J Mater Sci, 2001:36:5059.
 Chiu L H, Wu C H, Chang H. Cornvsion, 2007:63:127
 Mishra R, Balasubramaniam R. Corms Sci, 2004:46:3019.
 Cai J P, Lyon S B. Corms Sci, 2005:47:2956.