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چکیده
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The current work mainly aims at estimating the impact of reinforcement nanoparticles (NPs) of polytetrafluoroethylene (PTFE) on the electrochemical and mechanical characteristics of Ni-W-PTFE nanocomposite (NC) coatings. Ni-W-PTFE NC coating was electrodeposited on copper from a modified bath having PTFE particles by direct current (DC). The impact of PTFE NPs on characteristics of Ni-W coatings was studied. Energy-dispersive X-ray detector (EDS) coupled with SEM, scanning electron microscope (SEM), and XRD are employed to investigate the chemical composition, surface morphology, and grain size of Ni-W-PTFE NC coatings, respectively. The electrochemical behavior of deposits was analyzed by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (Tafel) techniques. It was found that the addition of PTFE particles enhanced the hardness and surface morphology of the composite coatings and changed to a more spherical granular shape. XRD results showed that the Ni-W/PTFE NC coating has a Face-Centered Cubic (FCC) structure and that the particle’s crystallite size range is 25 to 38 nm. In addition, corrosion tests displayed that at the first step, corrosion resistance of deposits was increased by increasing bath concentrations of PTFE (to 8 g L1 ). These superior properties are achieved chiefly due to uniformly distributed reinforced particles in deposits. The highest corrosion resistance (13293 X cm 2 ) was attained from the solution with 8 g L1 PTFE.
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