FIELD: corrosion protection.
SUBSTANCE: invention relates to aqueous solutions appropriate as liquid heat carriers for cooling circuits, for instance for internal combustion engine cooling systems. Polymetallic corrosion-inhibiting organic composition contains (i) 5-15% at least one unsaturated C10-C18-monocarboxylic acid or one of the salts thereof with alkali metal, amine selected from group including ethylamine, diethylamine, and triethylamine, or alkanolamine selected from group including monoethanolamine, diethanolamine, triethanolamine, or methyldiethanolamine; (ii) 40-70% at least one saturated carboxylic acids selected from group including saturated C5-C16-monocarboxylic acids and saturated C4-C12-dicarboxylic acids or salts thereof with alkali metal, amine, or alkanolamine; (iii) 20-40% tricarboxylic derivative of 1,3,5-triazine; and (iv) 1-5% azole derivative. Aqueous polymetallic corrosion-inhibiting composition contains 10 to 60 wt % of above-indicated organic inhibiting composition. Polymetallic corrosion-inhibiting antifreeze contains 0.1 to 10 wt % of the above aqueous inhibiting composition and 90 to 99.9 wt % of the water-alcohol solution with freezing temperature below 0єC, wherein alcohol is selected from group including methanol, ethanol, 2-propanol, glycerol, ethylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, and ethylene glycol methyl, ethyl, propyl and butyl ethers. Method of inhibiting polymetallic corrosion caused by liquid heat carriers comprises adding 3-6%, preferably 3.8-5%, of the above-indicated organic inhibiting composition to liquid heat carriers.
EFFECT: enhanced protection of parts made from various metals, in particular against cavitation corrosion.
11 cl, 2 tbl, 2 ex
