The anticorrosion properties of polymer emulsion modified cement-based coating with healing effect on carbon steel were investigated. The change of linear polarization resistance () and electrochemical impedance spectroscopy (EIS) have been used to measure the inhibitive and curative effect of electrodes painted with the coating in 3.5% NaCl solution. The results indicated the high alkalinity of filler (cement) in coating can obviously improve the anticorrosion performance of coated steel electrodes. And the inhibitive ability of cement-based coating with fluoride acrylic emulsion is superior to that of the coating with epoxy emulsion. Moreover, by adding antirust pigments and rust converters in the fluoride acrylic emulsion modified cement-based coating, the inhibitive property was improved and the curative effect can be observed.
Four kinds of alcohol amines were tested to improve the anticorrosion performance of the phosphoric and tannic acid (PTA)-based rust converter. The alcohol amine modified PTA rust converters with the optimum mechanical and functional performances were used to prepare the homogeneous single-component waterborne rust conversion-based paint. The mechanical properties and the long-term corrosion resistance of the synthesized rust converter-based paint were investigated. The results show that alcohol amine modified PTA rust converter can convert the rust layer into a thick passivation film with iron tannate and iron phosphate as the main components, significantly improving the corrosion resistance of the carbon steel. The alcohol amine D modified PTA rust converter (RC-D) showed the best anticorrosion and rust conversion performances. The waterborne rust conversion-based paint can convert the rust layer of steel into a blue-black and relatively flat passivation film layer. The waterborne polymer-based paint containing 10 wt.% RC-D significantly improves the long-term corrosion resistance of the rusty steel and the mechanical property of paint.
1 May 2016 in Journal of Materials in Civil Engineering
A mathematical model for the transport process of migrating corrosion inhibitor (MCI) in cement-based material and a two-dimensional numerical solution method using commercially-available software are proposed. The numerical analysis results are in a good agreement with experimental data obtained from the two-dimensional absorption tests for nonreactive MCI but do not coincide with the data for reactive MCI. The reason behind may be that the latter reacted with calcium hydroxide (CH) in cement mortar and hindered the transport process. Therefore a modified transport model involving the pore-blocking effect of reactive MCI in cement-based materials is established according to the chemometrics method. The numerical and test results prove that the amendatory model is reasonable to understand the mass transfer of reactive MCI in cement mortar. Variance analyses of the factors in the model are also performed to find the key factor affecting the MCI transport process. A basic transport model and numeric...
The roles of dielectric materials in adjusting the electromagnetic wave (EMW) absorption performance of an EMW absorber are as crucial as the EMW absorbents. The commonly used cement-based materials, such as mortar, are typical composites of multiple dielectric materials, such as quartz sand and air in the pores. This study investigates the EMW-absorption performances within the frequency range of 2 GHz to 18 GHz of cement paste and mortar samples with different sand-to-cement ratios (S/C), water-to-cement ratios (W/C), and thicknesses. The bow-frame method is used to measure the EMW reflection loss (RL) curves of slab-like samples. The coaxial method is used to record the electromagnetic parameters of the sample powders, which are also used to calculate the EMW RL curves. The results prove that the EMW-absorption performances of a slab-like mortar sample are monotonically related to the S/C ratio and the actual air volume, which is closely related to the thickness.