کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5363618 | 1388304 | 2011 | 6 صفحه PDF | دانلود رایگان |
Nanocrystalline Zn-Ni (crystallite sizes 13-68Â nm) alloy coatings were produced from an alkaline glycinate bath containing saccharin as additive. X-ray diffraction (XRD) was used to determine the phase composition and average crystallite size of nanocrystalline Zn-Ni alloy coatings. The average grain size of a deposit was also studied by transmission electron microscopy (TEM). The effects of saccharin concentration and current density on the crystallite size and surface roughness of the coatings were studied. Crystallite size and average surface roughness were diminished as a result of increasing saccharin concentration. Scanning electron microscopy (SEM) examination showed that coatings had a colony-like morphology and the colony size was increased with increasing current density. Microhardness testing was carried out in order to determine the degree of dependence of this mechanical property on the crystallite size. It was found that microhardness did not depend on crystallite size (Hall-Petch).
⺠Nanocrystalline Zn-Ni alloy was electrodeposited from alkaline bath in this research. ⺠The nanocrystalline deposit was synthesized with direct current only by modification of the bath. ⺠In addition to buffering and complexing, glycine added to the bath acted as a grain refiner. ⺠The microhardness of coatings did not depend on crystallite size via Hall-Petch equation.
Journal: Applied Surface Science - Volume 257, Issue 20, 1 August 2011, Pages 8311-8316