Sharif Digital Repository

Considerable researches have been focused on zinc-iron (Zn-Fe) alloy coatings due to their superior characteristics among zinc alloy electrodeposits in recent years. The corrosion behavior of these coatings depends on the phase structure and morphology of the Zn-Fe deposits. In this work the effects of pulse plating variables such as current density, off-time, frequency and pulse modes on the morphology and phase structure of Zn-Fe deposits was studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS) analysis. The corrosion behavior of these coatings was measured by means of polarization curves and Neutral salt spray tests. It was shown... 

A new Zinc phosphating bath, which produces coatings at relatively lower temperatures within a reasonable time by using of chemical accelerators has been devised. Improvement of the bath performance by the addition of divalent cations like calcium, nickel has been studied. Bath formulation and operating conditions have been optimized by coating weight determinations. Stable samples of phosphating formulations with and without calcium and nickel salts were prepared and the structure and morphology of the phosphate coatings were determined by using X-ray diffraction (XRD) techniques, scanning electron microscopy. ASTMB117 salt spray test and electrochemical impedance spectroscopy (EIS) were...