Effect of pyridine on the electrocrystallisation and corrosion behavior of Ni-W alloy coated from citrate-ammonia media

摘要

The effect of pyridine on coatings morphology, composition andcrystallographic orientation during electrodeposition of Ni-W layers from citrateammoniamedia onto copper substrate was investigated using SEM/EDS and XRD.The obtained Ni-W-Pyr layers were smoother, more compact and with finer grainsize. Furthermore, deposited film gives good crystalline structure with (200), (111)and (311) preferred orientations. Corrosion mechanisms and stability in 5h ofimmersion into 3% NaCl of various coatings were discussed in the consideration ofelectrical conductivity, microhardness, porosity, and inhibition efficiency.