| The new surface treatment technique of AMT-based compound passivators used for Brass is investigated in this paper. The technological process is developed by optimizing traditional pretreatment process, and the gas of nitrogen oxides is eliminated when nitric acid is replaced by sodium nitrate in acid cleaning solution. The treatment effect of AMT,BTA at different concentration and different temperature is researched by coupon testing in air. Through an orthogonal test, the effects of some factors, including time, temperature, the concentration of main inhibitors, on corrosion of brass and its corrosion resistance are studied in passivating solution using AMT and BTA as the main components. The corrosion resistance of samples after passivation is studied in the experiment by humid-air accelerated corrosion test, nitric acid titrating test and the brine dipping test. The passivator constitutes and craft term are: AMT:about 100mg/L BTA:about 200mg/L ethanol:about 1ml/L Na2WO4:about 50mg/L pH:7-8 surfactant temperature of passivation :about 45℃ the time of passivation :about 45min On the basis of studying inhibition performance, speed of forming film and effect of passivation treatment by electrochemical test, the effect mechanism of passivation is analyzed. Brass treated by the prime technique can nearly anti-discolor for 48h in humid-air accelerated corrosion test or for 4 months in the air at least. The technological process is so simple that unfamiliar operator could also operate. Consumption of chemical is little during passivation process, and the process could become simpler according to practical application. So it is a kind of alternative no-chromate passivation technique that can overcome the difficulty that chromate passivation is prohibited gradually but no effective technique can substitute it. It has a promising application foreground.
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