Author/Authors :
AllahKaram، S.R. نويسنده , , Faezi Alivand، R. نويسنده School of Metallurgy and Materials Engineering, University College of Engineering, University of Tehran, Tehran, Iran , , Bakhsh، M. S. نويسنده Department of material science engineeringe, South Tehran Branch , Islamic Azad University, Tehran, Iran ,
Abstract :
Electroless Nickel-phosphorus (EN) coatings provide high performance in various industrial fields due to
their unique properties such as excellent corrosion and wear resistance. This paper aims to study the effect of ZnO
nano-particles addition on corrosion behavior of EN coatings. Various amounts of ZnO nano-particles with average
diameter of 50 nm were added to hypophosphite reduced EN bath to deposit composite coatings. Microstructural
investigations were carried out via scanning electron microscopy (SEM). Chemical composition of the coatings was
investigated via energy dispersive spectroscopy (EDS). Electrochemical impedance spectroscopy (EIS) and
polarization tests were used to study the corrosion properties of the coatings in a 3.5 wt.% NaCl solution. SEM
investigations showed that the coating deposited from the bath containing 2 g/L of ZnO nano-particles had the most
amount of nano-particles incorporated in the coating. EDS results revealed that incorporation of ZnO nano-particles
in the composite coating resulted in a decrease in phosphorous content of the coating. Corrosion tests showed that
corrosion resistance of the electroless Ni-P/nanoZnO composite coatings in 3.5 wt.% NaCl solution had an
improvement in comparison to electroless Ni-P base coating.
