A New Type Of Rebar Corrosion Inhibition Agent Quenched At Low Temperature And Its Corrosion Resistant Mechanism

Two kinds of rebar corrosion inhibition quenched agent were prepared.Rebar quenched in the obtained agent at low temperature (110℃) can effectivelyinhibit the corrosion. The corrosion resistance of rebar was evaluated by theatmospheric exposure experiment (AE), wet and dry accelerated corrosionexperiment (CCT) and Tafel test. The corrosion resistant mechanism was alsoinvestigated by the SEM, XRD and FT-IR.The experiment results showed that the inhibition performance of the rebarwas improved with the increase of the the dosage of CMCNa and the decrease ofthe dosage of Na2CO3in sodium carboxymethyl cellulose system. The inhibitionperformance of the rebar was fistly increased and then unchanged with asincreasing the the dosage of Na2MoO4and Na2O nSiO2. The appropriate dosagesof each component were as follows:0.3wt%of CMCNa,1wt%of Na2CO3,0.02wt%of Na2MoO4,9wt%of Na2O nSiO2. The inhibition efficiency of rebarquenched with the agent reached50.7%and50.3%for atmospheric exposurecorrosion46days and alternating wet and dry10cycles, respectively. The Tafeltest results showed that the inhibition efficiency of rebar reached93.6%, theobtained inhibition agent was a kind of mixed type corrosion inhibitor. When thecivilian water was used as the solvent of corrosion inhibition quenched agent, thecorrosion inhibition rate for atmospheric exposed corrosion was10%lower thanthat deionized water as solvent.The inhibition performance of the rebar was improved with the increase ofthe dosage of PAAS and Na2O·nSiO2, and was fistly improved and thenunchanged with the increase of the dosage of C6H18O24P6(aq)(≧70%) andN(CH2CH2OH)3in sodium polyacrylate system. The appropriate dosages of eachcomponent were as follows:0.3wt%of PAAS,0.2wt%of C6H18O24P6(aq),10wt%of Na2O·nSiO2,0.4wt%of N(CH2CH2OH)3. The inhibition efficiency ofrebar quenched with the agent reached68.2%and66.7%for atmosphericexposure corrosion27days and alternating wet and dry28cycles, respectively.The Tafel test results showed that the inhibition efficiency of rebar reached69%,the obtained inhibition agent was a kind of anode type corrosion inhibitor. Theelectrochemical tests showed that the activation energy of the corrosion reactionincreased from73.8kJ/mol to111.3kJ/mol after quenched by the agent, whichproved that the corrosion reaction was effectively suppressed. SEM, XRD and FTIR studies showed that the composition of the atmospheric corrosion productsstill consisted of α-Fe2O3, γ-Fe2O3, α-FeOOH and the compound contained iron、silicon and oxide, and the relative content of each composition has changed.