Study On The Corrosion Resistance Of Electric Arc Spraying Zn-Al Based Alloy Coatings

The corrosion behavior and corrosion resistance of Zn-Al, Zn-Al-Re andZn-Al-Mg-Re alloy coatings were investigated by means of salt spray test andimmersion test. By SEM, XRD and polarization curves, electrochemical impedancespectroscopy to observe and analyze the Zn-Al，Zn-Al-Re and Zn-Al-Mg-Re alloycoatings. We studied the surface of corrosion morphology and electrochemical laws foralloy coatings.This paper had carried out corrosion test for Zn-Al alloy coatings, Zn-Al-Re alloycoatings and Zn-Al-Mg-Re alloy coatings indoor salt spray test. The samples wererecorded the corrosion potential and observed the corrosion morphology changes. Andthe results of Zn-Al-Re alloy coatings and Zn-Al-Mg-Re alloy coatings were comparedwith Zn-Al alloy coatings. The conclusion was that their corrosion resistances werebetter than that of Zn-Al alloy coatings. On the basis of the salt spray test, the paper hadcarried out immersion test for Zn-Al alloy coatings, Zn-Al-Re alloy coatings andZn-Al-Mg-Re alloy coatings. The samples were recorded the corrosion potential andobserve the corrosion morphology changes to verify the corrosion resistance ofZn-Al-Re and Zn-Al-Mg-Re alloy coatings.The results show that Zn-Al-Re alloy coatings and Zn-Al-Mg-Re alloy coatingshave dense coating and strong substrate adhesion, a lower corrosion potential. And thecorrosion resistance is greatly improved compared to of Zn-Al alloy coatings. The maincorrosion products of Zn-Al-Re alloy coatings and Zn-Al-Mg-Re alloy coatings arecompounds of Zn, Al and Re、Mg, which improve the self-sealing effectiveness.