Corrosion Resistance of Three Arc-sprayed Zinc Coatings in 3.5% NaCl Solution

Pure Zn, Zn-Al alloy and Zn-Al pseudo-alloy coatings were prepared on Q235 steel surface by arc spraying technique. The corrosion resistance of these coatings was investigated by immersion testing and electrochemical measurements in 3.5% NaCl solution. The surface morphology of the samples after test and the phase composition of corrosion products were analyzed by using electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the corrosion resistance of the coatings decreased sequentially in the order of Zn-Al pseudo alloy coating, Zn-Al alloy coating, and pure Zn coating.