A series of water based environmental-friendly fluxes were prepared with succinic acid and malic acid compounded (w=2.00%) as activator

glycol

isopropanol and ethylene glycol butyl ether compounded (w=3.00%) as co-solvent

polyethylene glycol 6000(w=0.25%) as film-forming reagent

and imidazole (IM)

benzimidazole (BIA)

benzotriazole (BTA) as corrosion inhibitor respectively. The corrosion inhibition performance of imidazole

benzimidazole

benzotriazole on the copper in the flux was investigated with the static weight-loss method

electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). Corrosion inhibition efficiency increased firstly with the increase of concentration of inhibitor

but decreased over the optimum concentration. With 0.08% benzotriazole as inhibitor

the inhibiting rate was up to 88.78%

metal film resistance Rf was up to1.25×106 Ω·cm2

and the flux showed better corrosion inhibition. The research also indicated that inhibiting rate was up to 94.25% and Rf was up to 2.26×106 Ω·cm2

when the content of the compounded inhibitor remained as 0.08% and the mass ratio of BIA and BTA was 1:1 in the flux. These results indicated that there was a good synergistic effect after BIA and BTA compounded as inhibitor. A tight absorbed protective film was formed after the addition of compounded corrosion inhibitors together

which might be the main reason that inhibited and reduced copper corrosion. The data of spreading area of flux also indicated that the suitable amount of compounded corrosion inhibitors was 0.04% BIA and 0.04% BTA.