The Study of Electroless Ni-Cu-P Plating on Corrosion Resistance of Aluminium in 3.5% NaCl
1SCHOOL OF CHEMICAL SCIENCES, UNIVERSITI SAINS MALAYSIA, Gelugor, Penang, Malaysia
2School of Mathematics and Basic Sciences, Quest International University Perak, Ipoh, Perak, Malaysia
3School of Chemical Sciences, Universiti Sains Malaysia, Gelugor, Penang, Malaysia
*Email Address : mhh@usm.my
Abstract : Corrosion resistance studies of electroless Ni-Cu-P composite coatings on aluminium substrate at different conditions; concentration of NaH2PO2·H2O, pH and immersion time. The corrosion resistance studies of the uncoated and coated aluminium substrates were investigated in 3.5 % (w/v) of NaCl solution by potentiodynamic polarization (PD) and electrochemical impedance spectroscopy (EIS) techniques. Further study on the composition of coated aluminium substrate and its microstructure were observed by various analyses techniques such SEM, EDX, XRD and AFM. Based on the results, the highest inhibition efficiency was attained at 80% when the concentration of NaH2PO2·H2O used was 120 g L-1 at pH 9 and 60 mins of immersion time. The XRD analysis confirmed the presence of the Ni-Cu-P elements on the aluminium substrate surface and the AFM measurements showed that Ni-Cu-P layer improved the surface smoothness of the substrate. The paper provides information on different conditions; concentration of NaH2PO2·H2O, pH and immersion time.
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