Corrosion Of Cold Rolled Steel Research Articles

Adsorption and inhibition of rosin thiourea imidazole quaternary ammonium salt on steel surface in HCl solution

Rosin thiourea imidazole quaternary ammonium salt (RTIQAs) was synthesized by connecting rosin and imidazole units via thiourea linker, and its inhibitive action on the corrosion of CRS (cold rolled steel) in 1.0 M HCl solution was fully investigated. The results demonstrate that RTIQAs is an efficient mixed-type inhibitor with the maximum inhibition efficiency of 95%. The adsorption rule on the CRS surface fully complies with Langmuir isotherm. The efficient inhibition of RTIQAs can also be verified by AFM, SEM and CLSM (confocal laser scanning microscope). The direct adsorption proof of RTIQAs molecules on steel surface can be further presented in EDX and XPS.

Inhibition action of triazolyl blue tetrazolium bromide on cold rolled steel corrosion in three chlorinated acetic acids

The inhibition effect of triazolyl blue tetrazolium bromide (TBTB) on cold rolled steel (CRS) in three chlorinated acetic acids of monochloroacetic acid (ClCH2COOH), dichloroacetic acid (Cl2CHCOOH) and trichloroacetic acid (Cl3CCOOH) was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. Meanwhile, the adsorption mechanism of TBT+ (organic part of TBTB) was theoretically investigated by quantum chemical calculation and molecular dynamics (MD) simulations. The results show that TBTB acts as a good inhibitor, and inhibition efficiency in three chlorinated acetic acids follows the order: ClCH2COOH < Cl2CHCOOH < Cl3CCOOH. The maximum inhibition efficiency of 1.0 mM TBTB from weight loss method is 85.8% in ClCH2COOH; 91.7% in Cl2CHCOOH; and 95.5% in Cl3CCOOH. The adsorption of TBTB on CRS surface obeys Langmuir isotherm, and the adsorption free energy (ΔG0) is about −34 kJ mol−1. In each chlorinated acetic acid solution, TBTB behaves as a mixed inhibitor, and the presence of TBTB shifts the both anodic and cathodic curves to lower current densities. With the addition of TBTB, the corrosion potential almost does not alter in ClCH2COOH, while becomes more positive in Cl2CHCOOH, and moves negative position in Cl3CCOOH. EIS exhibits one large depressed capacitive loop at high frequencies followed by a small inductive section at low frequencies. In the presence of TBTB, the charge transfer resistance increases, while both constant phase element and double layer capacitance decreases. SEM micrographs reveal that the corrosion of CRS can be efficiently retarded by TBTB. TBT+ can be further protonated by H+ in acid solution to form TBTH2+. Both TBTH2+ and TBT+ could easily physical adsorb on steel surface owing to high dipole moment values, and TBTH2+ exhibits stronger physisorption than TBT+. The electron densities of both HOMO and LUMO are localized principally on tetrazole and thiazole rings, which are chemical adsorption sites. TBTH2+ strengthens accepting electrons while weakens donating electrons as compared with TBT+. Both TBT+ and TBTH2+ adsorb onto Fe (001) surface with nearly flat orientation mode, and the adsorption energy of TBT+ is a little higher than that of TBTH2+.

Corrosion Inhibition of 2-Aminopyrimidine for Steel in Hydrochloric Acid Media

The inhibition effect of 2-aminopyrimidine(2-AP) on the corrosion of cold rolled steel(CRS) in 1.0~5.0 mol/L HCl media at 20~50 ℃ has been studied by mass loss,potentiodynamic polarization curves and electrochemical impedance spectroscopy(EIS) methods.The results showed that the neutral 2-AP is a good inhibitor for CRS,and the adsorption of 2-AP on the CRS surface follows the amended Langmuir adsorption isotherm equation.Inhibition efficiency increases with the inhibitor concentration,while decreases with temperature and the concentration of HCl.Polarization curves showed that 2-AP is a mixed-type inhibitor.EIS spectra exhibited one capacitive loop,and the charge transfer resistance increased with the inhibitor 2-AP concentration.

Two pyrazine derivatives as inhibitors of the cold rolled steel corrosion in hydrochloric acid solution

The inhibition effect of two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) on the corrosion of cold rolled steel (CRS) in 1.0 M hydrochloric acid (HCl) was studied by weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results show that both AP and ABP are good inhibitors, and inhibition efficiency follows the order: ABP > AP. The adsorption of each inhibitor on CRS surface obeys Langmuir adsorption isotherm. Potentiodynamic polarization curves show that two pyrazine derivatives act as mixed-type inhibitors. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability.

Inhibition of cold rolled steel corrosion in sulphuric acid solution by 2-mercapto-1-methylimidazole: Time and temperature effects treatments

2-Mercapto-1-methylimidazole (MMI) has been evaluated as a corrosion inhibitor for cold rolled steel in aerated 2M H2SO4 by gravimetric method. The effect of MMI on the corrosion rate was determined at various immersions time and concentrations. The effect of the temperature on the corrosion behaviour with addition of different concentrations of MMI was studied in the temperature range 30–60°C. The MMI acts as an effective corrosion inhibitor for cold rolled in sulphuric acid medium. The inhibition process is attributed to the formation of an adsorbed film of MMI on the metal surface which protects the metal against corrosion. The protection efficiency increased with increase in inhibitor concentration at various immersions time and decreased with increase in temperature. Adsorption of MMI on the cold rolled steel surface is found to obey the Langmuir adsorption isotherm. Some thermodynamic functions of dissolution and adsorption processes were also determined.

Synergistic Inhibition Effect of Rare Earth Ce4+ and Vanillin on the Corrosion of Cold Rolled Steel in H3PO4 Media

Synergistic Inhibition Effect of Rare Earth Ce4+ and Vanillin on the Corrosion of Cold Rolled Steel in H3PO4 Media

Synergistic inhibition between dodecylamine and potassium iodide on the corrosion of cold rolled steel in 0.1 M phosphoric acid

AbstractThe corrosion inhibition of cold rolled steel in 0.1 M aerated phosphoric acid (H3PO4) in the presence of dodecylamine (DDA) and potassium iodide (KI) has been investigated by Tafel polarization curve and electrochemical impedence spectroscopy (EIS) at 20 °C. The results obtained from polarization curve show that the inhibition efficiency of DDA with and without KI increases with increase in concentration of DDA but the inhibition efficiency of DDA without KI is not too high. A synergistic effect exists when DDA and KI are combined together to prevent cold rolled steel corrosion in 0.1 M H3PO4. All impedance spectra in EIS tests exhibit one capacitive loop which indicates that the corrosion reaction is controlled by charge transfer process. Inhibition efficiencies obtained from Tafel polarization, transfer resistance (Rt) are consistent.

The synergistic inhibition of the cold rolled steel Corrosion in 0.5 M sulfuric acid by the mixture of OP and bromide ion

The synergistic inhibitive effect of the mixture of OP and NaBr on the corrosion of cold rolled steel in 0.5 M sulfuric acid has been investigated using weight loss and polarization method. The results reveal that corrosion of cold rolled steel has been efficiently inhibited by OP in the presence of NaBr in sulfuric acid, and inhibition efficiency increases with increasing concentration of OP at a constant temperature. A synergistic effect has been observed for OP with NaBr at all investigated temperatures (except 30 °C). The polarization curves show that the mixture of OP and NaBr is a cathodic inhibitor. The experimental results suggest that the presence of bromide ion in the solution stabilizes the adsorption of OP molecules on the metal surface and improves the inhibition efficiency of OP. Langmuir adsorption isotherm equation is obeyed at all the temperatures studied. The results obtained from weight loss and polarization method are in good agreement. The present study is important for the practical use of surfactant as corrosion inhibitor for steel in acidic media.

The synergistic inhibition effect of rare earth cerium(IV) ion and iso-vanillin on the corrosion of cold rolled steel in 1.0 M H 2SO 4 solution

The synergistic inhibition effect of rare earth cerium(IV) ion and iso-vanillin (3-hydroxy-4-methoxy-benzaldehyde) on the corrosion of cold rolled steel (CRS) in 1.0 M H 2SO 4 solution was first investigated by weight loss and potentiodynamic polarization methods. The results revealed that iso-vanillin had a moderate inhibitive effect on the corrosion of CRS in 1.0 M H 2SO 4 solution, while cerium(IV) ion had a negligible effect. However, incorporation of Ce 4+ with iso-vanillin significantly improved the inhibition performance. The inhibition efficiency for Ce 4+ in combination with iso-vanillin was higher than the summation of inhibition efficiency for single Ce 4+ and single iso-vanillin, which was synergism in nature.

The synergistic inhibition between 8-hydroxyquinoline and chloride ion for the corrosion of cold rolled steel in 0.5 M sulfuric acid

The corrosion inhibition of cold rolled steel in 0.5 M sulfuric acid in the presence of 8-hydroxyquinoline and sodium chloride (NaCl) has been investigated by using weight loss and electrochemical techniques. The inhibition efficiency increases with increasing concentration of 8-hydroxyquinoline at the same temperature, but decreases with increasing temperature studied. A synergistic effect exists when 8-hydroxyquinoline and chloride ions are used together to prevent cold rolled steel corrosion in 0.5 M sulfuric acid at every experimental temperature. The polarization curves show that 8-hydroxyquinoline is a cathodic inhibitor, while the complex of 8-hydroxyquinoline and NaCl is a mixed-type inhibitor. The experimental results suggested that the presence of chloride ions in the solution stabilizes the adsorption of 8-hydroxyquinoline molecules on the metal surface and improved the inhibition efficiency of 8-hydroxyquinoline. The adsorption of single 8-hydroxyquinoline follows the Temkin adsorption isotherm, but the complex accords with the Langmuir adsorption isotherm. Some thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy have been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have been calculated and discussed.

Inhibition of cold rolled steel corrosion by Tween-20 in sulfuric acid: Weight loss, electrochemical and AFM approaches

The inhibiting action of a nonionic surfactant of Tween-20 on the corrosion of cold rolled steel (CRS) in 0.5–7.0 M sulfuric acid (H 2SO 4) was studied by weight loss and potentiodynamic polarization methods. Atomic force microscope (AFM) provided the surface conditions. The results show that inhibition efficiency increases with the inhibitor concentration, while it decreases with the sulfuric acid concentration. The adsorption of inhibitor on the cold rolled steel surface obeys the Langmuir adsorption isotherm equation. Effect of immersion time was studied and discussed. The effect of temperature on the corrosion behavior of cold rolled steel was also studied at four temperatures ranging from 30 to 60 °C, the thermodynamic parameters such as adsorption heat, adsorption free energy, and adsorption entropy were calculated. The results revealed that the adsorption was physisorption mechanism. A kinetic study of cold rolled steel in uninhibited and inhibited acid was also discussed. The kinetic parameters such as apparent activation energy, pre-exponential factor, rate constant, and reaction constant were calculated for the reactions of corrosion. The inhibition effect is satisfactorily explained by both thermodynamic and kinetic models. Polarization curves show that Tween-20 is a cathodic-type inhibitor in sulfuric acid. The results obtained from weight loss and potentiodynamic polarization are in good agreement, and the Tween-20 inhibition action could also be evidenced by surface AFM images.

Synergistic inhibition between o-phenanthroline and chloride ion for steel corrosion in sulphuric acid

The corrosion inhibition of cold rolled steel in 0.5 M sulphuric acid in the presence of o-phenanthroline and sodium chloride (NaCl) has been investigated by using weight loss and electrochemical techniques. The experimental data suggest that the inhibition efficiency increases with increasing NaCl concentration in the presence of 0.0002 M o-phenanthroline, but decreases with increasing temperature. A synergistic effect is observed when o-phenanthroline and chloride ions are used together to prevent cold rolled steel corrosion in 0.5 M sulphuric acid. The polarization curves showed that the complex of o-phenanthroline and NaCl acts as a mixed type inhibitor. The experimental results suggested that the presence of chloride ions in the solution stabilized the adsorption of o-phenanthroline molecules on the metal surface and improved the inhibition efficiency of o-phenanthroline. The adsorption of the complex accords with the Langmuir adsorption isotherm. Some thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy have been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have been calculated and discussed.

Synergistic inhibition between tween 60 and NaCl on the corrosion of cold rolled steel in 0.5 M sulfuric acid

The corrosion inhibition of cold rolled steel in 0.5 M sulfuric acid in the presence of tween 60 and sodium chloride (NaCl) has been investigated by using weight loss and electrochemical techniques. The inhibition efficiency increases with increasing tween 60 concentration at the same temperature, but decreases with increasing temperature studied. A synergistic effect exists when tween 60 and chloride ions are used together to prevent cold rolled steel corrosion in 0.5 M sulfuric acid at every experimental temperature. The polarization curves show that tween 60 is a cathodic inhibitor, while the complex of tween 60 and NaCl is a mixed-type inhibitor. The experimental results suggest that the presence of chloride ions in the solution stabilizes the adsorption of tween 60 molecules on the metal surface and improves the inhibition efficiency of tween 60. The adsorption of single tween 60 follows the Temkin adsorption isotherm, but the complex accords with the Langmuir adsorption isotherm. Some thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy has been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have been calculated and discussed.

Synergistic inhibition between OP and NaCl on the corrosion of cold-rolled steel in phosphoric acid

The effects of single OP and the mixture of various concentrations of OP and 0.1 M NaCl on the corrosion of cold-rolled steel in 1.0–3.5 M phosphoric acid have been investigated by using weight loss method and polarization method. This study revealed that cold-rolled steel in phosphoric acid has been more efficiently inhibited by OP in the presence of NaCl than single OP, and inhibition efficiency increases with increasing concentration of OP at the same temperature, but decreases with increasing temperature studied. A synergistic effect exists when OP and chloride ion are used together to prevent cold-rolled steel corrosion in 1.0–3.5 M phosphoric acid at every experimental temperature. The polarization curves showed that OP is a cathodic inhibitor, while the complex of OP and NaCl is a mixed-type inhibitor that mainly inhibits the cathodic corrosion of the steel. The experimental results suggested that the presence of chloride ion in the solution stabilized the adsorption of OP molecules on the metal surface and improved the inhibition efficiency of OP. The adsorption of single OP follows the Langmuir adsorption isotherm, and the adsorption of the complex accords with the Langmuir adsorption isotherm too. Some thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy have been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have been calculated and discussed. In 1.5–3.5 M phosphoric acid, the concentration pre-exponential factor and acid concentration constant have been calculated, and the synergistic effect has been observed too.

Synergistic inhibition between o-phenanthroline and chloride ion on cold rolled steel corrosion in phosphoric acid

Synergistic inhibition between o-phenanthroline and chloride ion on cold rolled steel corrosion in phosphoric acid

Synergistic inhibition between o-phenanthroline and chloride ion on cold rolled steel corrosion in phosphoric acid

The effects of single o-phenanthroline and the mixture of various concentrations of NaCl and 0.0002 M o-phenanthroline on the corrosion of cold rolled steel in 1.0–4.0 M phosphoric acid have been investigated by using weight loss method and polarization method. The present study revealed that cold rolled steel in phosphoric acid has been more efficiently inhibited by o-phenanthroline in the presence of NaCl than single o-phenanthroline, and inhibition efficiency increases with increasing concentration of NaCl in the presence of 0.0002 M o-phenanthroline. At a relative higher concentration of NaCl, there is the synergistic effect between o-phenanthroline and NaCl. The adsorption of inhibitor accords with the Langmuir adsorption isotherm. Polarization studies show that the inhibitor mainly acts as a mixed type inhibitor for steel in 1.0 M phosphoric acid. Thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy are obtained from experimental data of the temperature studies of the inhibition process at four temperatures ranging from 30 to 45 °C. The kinetic data such as apparent activation energy and pre-exponential factor at different concentrations of the inhibitor are calculated, and the effects of the apparent activation energy and pre-exponential factor on the corrosion rate of cold rolled steel are discussed. At 40 °C, in 1.5–4.0 M phosphoric acid, the concentration pre-exponential factor and acid concentration constant are calculated, the synergistic effect has been observed too, and the inhibition efficiency of mixture slowly decreases with increasing concentration of phosphoric acid. A new equation has been used to explain the dependence of corrosion rate on acid concentration. The inhibition action is satisfactorily explained by using both thermodynamic and kinetic models. The results obtained from weight loss method and polarization method are in good agreement.

Thermal-wave imaging of the microstructure and corrosion of cold-rolled steel under protective coatings

Thermal-wave imaging of the microstructure and corrosion of cold-rolled steel under protective coatings

Thermal-wave microscopy and its application to imaging the microstructure and corrosion of cold-rolled steel

Thermal-wave microscopy (TWM), which employs heat flow to probe variations in the thermal properties of solid materials, can provide micron-level resolutions of subsurface features of opaque samples, this paper describes the principle of TWM, reviews its applications in material science, and presents the results of studies using this technique to imaging the microstructure and corrosion of cold-rolled steels. Preliminary results indicate that TWM can image the microstructure of cold-rolled steel with or without a corrosion layer. The results obtained also suggest that the technique can monitor and assess corrosion in its early stage of formation.