Research On Mechanism And Effect Of Rust Inhibitor

Presently, organic composite steel corrosion inhibitor is the most promisingcorrosion inhibitor despite of its complex components and various brands. In relevantresearches, scholars hold divergent opinions upon its anticorrosion performance andmechanism. This thesis starts with its impact upon physical properties of the concrete andupon steel corrosion, firstly applying RCM experiments, SEM and XRD phase analysis toevaluate the influences of corrosion inhibitor towards concrete compactness. We try todefine its inhibiting effects to the permeation of harmful ions and explore how corrosioninhibitor change the physical properties of concrete. Secondly, we employ reinforcedbrine immersion test, steel-concrete soak drying test and steel surface morphologyobservation to evaluate how inhibitor slows corrosion, analyze its influence upon steelsurface passivation membrane density and summarize anticorrosion mechanism. Finally,electrochemical experiments are used to find the most proper compound mode from thecomparison of the influences of different inhibitor contents to steel existing insimulated pore solution. The conclusion are as following:（1）Organic corrosion inhibitor could lower diffusion coefficient of chloride ions.Inner introduced corrosion inhibitor, outer coating inhibitor, and inhibitor which appliesboth inner and outer anticorrosion product could respectively lower diffusion coefficientof chloride ions with16.8%、17.3%、23.5%compared with control group.（2）XRD phase analysis shows that inner inhibitor lowers the diffraction peak ofC3S and Ca(OH)2in the concrete and stimulates the hydration of the cement, whichimplies that it contains water reducing content. Therefore, before actual engineerapplication, we should emphasize its compatibility with other additives to ensure zeroharmful effects to the physical properties of concrete.（3）The mechanism of anticorrosion in experiments are:①the stimulation of thehydration of concrete and the formation of precipitation in tiny concrete pores couldincrease the density of concrete to reduce the invasion of harmful ions.②inhibitormolecules adsorb on steel to form compact passivation coating to increase criticalchloride concentration. （4）Steel corrosion inhibitor could obviously prevent corrosion in concrete. Soakdrying test demonstrates that inner introduced corrosion inhibitor, outer coating inhibitor,and inhibitor which applies both inner and outer anticorrosion product could respectivelylower steel corrosion ratio by43.3%、51.3%、64.5%compares with control group.（5） We could find out the optimal adding mode of inhibitor from different addingmode inhibitors in simulated pore solution. Immersion test, EIS test and Tafelpolarization curve test all show that adding inner and outer anticorrosion productsimultaneously at the beginning could prevent corrosion the most efficiently withinhibiting ratios of50.8%、54.1%、45.6%.