Influence of Annealing on Crystallinity of Electroless Ni-P Deposits
Keywords:
Electroless nickel, Annealing, Crystallization, XRD, Profile Analysis.Abstract
Electroless nickel is one of the widespread commercial and industrial coatings owing to its unique properties, such as good wear and corrosion resistance, thickness uniformity etc. The crystallinity of the deposits is one of the important factors which are influencing the properties. In this investigation, electroless Ni-P is deposited on mild steel substrate. The deposits were annealed at various temperatures for 2 hours. The crystallization process of these deposits was studied using single line profile analysis, employing pseudo-Voigt profile function. To de-convolute the overlapped reflections from different phases PRO-FIT software package was used. The data which are taken from the X-ray diffraction profile was used to find the crystallite size and microstrain using the in-house software ‘PROFAN’. The XRD reveals the formation Ni3P at and above 3000C. The amorphous phase becomes unstable and more or less disappears around 3600C which confirms the completion of recrystallization. The crystallite size increased sharply above 360°C, accompanied by a steep reduction in the microstrain, indicating the onset of precipitation.
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