%0 Journal Article
%T EIS STUDY ON THE EFFECTS OF HEAT TREATMENT ON CORROSION BEHAVIOR OF NICKEL BASE ALLOY COATING<br>
%A Yong Wang
%A <br>
%J 金属学报
%D 2008
%I 
%X NiCrBSi alloy powders were sprayed on a low carbon steel substrate using High velocity oxy-fuel (HVOF) spraying technique and then the samples with coating were heat treated in air furnace for 2h or 10min at 900°C. The corrosion failure process and corrosion resistance of coatings in 3.5% NaCl aqueous solution were investigated by using Electrochemical Impedance Spectroscope (EIS). EIS data shows that the as-sprayed coating cannot resist the penetration of corrosive solution and after 20h the steel substrate begins to be corroded. Local corrosion happens in 2h heat-treated coating if contacting coating with brine longer than 15h, while shape of EIS plots can hold stable for a long time and uniform corrosion happens in 10min heat-treated coating. Relationship of corrosion resistance with time for as-sprayed coating and heat-treated coatings in 3.5% NaCl was obtained using equivalent circuits. The corrosion resistance of 10min heat-treated coating and resistance to penetration of aqueous medium are far better than of as-sprayed coating, but the corrosion resistance of heat-treated coatings with long holding time (2h) is inferior to that of as-sprayed coating. The reasons why heat treatment can change the corrosion behavior of sprayed coating were discussed by the aid of analyzing microstructure.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=AB188D3B70B071C57EB64E395D864ECE&jid=B061E1135F1CBDEE96CD96C109FEAD65&aid=9C09790161794D155BDA3435458D69FC&yid=67289AFF6305E306&vid=1AE5323881A5ECDC&iid=9CF7A0430CBB2DFD&sid=D3CBA54FACB30BD9&eid=005F3549A8D9454D&journal_id=0412-1961&journal_name=金属学报&referenced_num=0&reference_num=0