The Corrosion Behavior Research Of Non-silicon Antifreezing To Different Materials

As the core component of automobile,the engine of cars provides power for it.Because of the huge heat exchange during the process,cooling system is needed to lower the temperature of the engine.One of the effects of why antifreezing exits is to lower the temperature of the engine,and another effect is to prevent the material of engine from being destroyed by the low temperature in cold winter.Normally,antifreezing is composed of glycol and water by certain ratio,and the engine of car can be made of many materials,such as carbon steel,aluminium alloy,magnesium alloy and so on.So corrosion is really a serious problem in car’s cooling system,especially the corrosion of material caused by antifreezing.Usually,the way to solve the problem is to add inhibitors in antifreezing.Most of commercially antifreezings sold in market contain silicate corrosion inhibitors.However,the biggest drawback of silicate is its instability,which means flocs will appear after a period of time using.So this paper mainly studies the formula of corrosion inhibitor without silicate.In this paper,compounding of organics and inorganics inhibitors is used to reduce corrosion of different materials.We mainly studied corrosion inhibition circumstance of 20#carbon steel,1050 pure aluminium,AZ31B magnesium alloy,and we found an effective corrosion inhibitor formula and its application condition.Experiment conclusions are as followed:1.Boride,benzoic acid salt,organic acids,nitrogen compounds,fluoride and organic amine are used as compound corrosion inhibitor.L25(56)orthogonal test table are used to choose formula,and the conditions are at normal temperature using electrochemical potentiodynamic scanning polarization curve testing 20#carbon steel.After choosing two better formulas,we continue doing electrochemical experiments and corrosion weightlessness experiments with 20#carbon steel,1050 pure aluminium,AZ31B magnesium alloy.Finally we got one corrosion inhibitor formulations that is the most effective to all three alloys.2.Adding pH buffering agent to the formula solution,we tested the corrosion inhibition of the formula solution to three kinds of alloy under the condition of different pH,and we found the best pH effect of corrosion inhibition of formula solution to 20#carbon steel,1050 pure aluminium and AZ31B magnesium alloy respectively is pH = 6.6,pH = 7.0 and pH = 7.5.3.We tested the corrosion inhibition of the formula solution to three kinds of alloy under the condition of 30%,40%,50%,60%glycol concentration,and we found the best glycol concentration effect of corrosion inhibition of formula solution to 20#carbon steel,1050 pure aluminium and AZ31B magnesium alloy respectively is 30%,60%and 60%.4.We tested the application of the formula solution in 0℃,20℃,40℃,60℃ and 80℃ temperature,and we found the corrosion inhibition of formula solution to 20#carbon steel in more than 20 ℃ high temperature is ideal;to 1050 pure aluminum in less than 20℃ low temperature is ideal;to AZ31B magnesium alloy under the condition of 0-80℃ temperature range all has effective corrosion inhibition.