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The purpose of this paper is to investigate the effects of several azole derivatives on the corrosion inhibition of irradiated and non‐irradiated plain carbon steel in 0.5 M nitric acid (HNO₃) solutions at 30‐60°C and to study the mechanism of their inhibitive action.

The inhibition efficiency was evaluated by means of weight‐loss determinations and polarization techniques at different temperatures. The type of adsorption isotherm, inhibition efficiency, surface coverage and kinetic data were determined.

The results showed that azole derivatives inhibit the corrosion of irradiated and non‐irradiated carbon steel in acidic solution. The inhibition efficiency increased with the inhibitor concentration and was greater in the case of irradiated carbon steel than for the non‐irradiated one. Kinetic parameters were calculated. The adsorption of inhibitors obeyed the Temkin Isotherm model. Thermodynamic parameters of activation were calculated in the presence of inhibitors.

Electrochemical studies such as electrochemical impedance spectra will throw more light on the mechanism of inhibition.

Azole derivatives can be used as inhibitors in acid medium and addition of halides can improve their inhibition efficiency.

The investigation revealed the possible application of azole derivatives as environmentally friendly inhibitors for corrosion prevention under specific conditions.

The purpose of this paper is investigate the inhibition efficiency of three similar bi-cyclic organic compounds, namely, benzimidazole (BI), benzotriazole (BTAH) and benzothiazole (BTH) on carbon steel in 1 M hydrochloric acid (HCl) solution. Organic inhibitors are widely used to protect metals in acidic media. Among abundant suggestions for acid corrosion inhibitors, azole compounds have gained attention.

The inhibition efficiency of the three organic compounds was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS).

Superiorities of BTH and BTAH corrosion inhibitors were shown by EIS data and polarization curves. Moreover, the results revealed that BTAH and BTH can function as effective mixed-type adsorptive inhibitors, whereas no inhibition behavior was observed for BI. Both BTAH and BTH obeyed Longmuir adsorption isotherm. The results obtained from this isotherm showed that both inhibitors adsorbed on the specimen surface physically and chemically. The difference in inhibition efficiencies of BTAH, BTH and BI was related to the presence of nitrogen and sulfur hetero atoms on their molecular structures.

This study evaluated inhibition efficiency of BI, BTAH and BTH using electrochemical methods. In addition, the study attempted to find inhibition mechanism of the inhibitors and to find modes of adsorption of the inhibitors, correlating effects of heteroatoms and inhibition efficiency.

This study attempts to investigate corrosion inhibition properties of 1H-benzimidazole (B) and 1H-benzotriazole (BTA) on aluminum in 0.25 M HCl solution at different concentrations.

To this end, electrochemical techniques including electrochemical noise (EN), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were used.

Results showed a greater corrosion inhibition efficiency of BTA than B on aluminum in HCl solution. BTA showed greater tendency to adsorption on the metal surface than B because of the inclusion of three nitrogen atoms.

The novelty of this work is comparing EN data with EIS and potentiodynamic polarization parameters.

Copper and its alloys are widely used in industries because of their good resistance to corrosion and are often used in cooling water systems. Brass has been widely used for shipboard condensers, power plant condensers and petrochemical heat exchangers. Brass is susceptible to the corrosion process known as dezincification by means of which brass looses its valuable physical and mechanical properties leading to failure of structure. The aim of this investigation was to control the dezincification of brass in 3 per cent NaCl solution using benzotriazole (BTA) derivatives.

BTA derivatives namely 1‐hydroxymethylbenzotriazole (HBTA) and N,N‐dibenzotriazol‐l‐ylmethylamine(ABTA) were synthesised and their inhibition behaviour on brass in 3 per cent NaCl solution was investigated by the weight‐loss method, potentiodynamic polarisation, electrochemical impedance and solution analysis techniques. The morphology of the brass after corrosion in the presence and absence of the BTA derivatives was examined using scanning electron microscopy (SEM).

Potentiodynamic polarisation studies showed that the BTA derivatives investigated were mixed type inhibitors, inhibiting the corrosion of brass by blocking the active sites of the brass surface. Changes in the impedance parameters (charge transfer resistance and double layer capacitance) were related to the adsorption of BTA derivatives on the brass surface, leading to the formation of a protective film. Solution analysis revealed that the BTA derivatives excellently controlled the corrosion of brass. SEM micrographs showed the formation of compact surface film on the brass surface in the presence of inhibitors, thereby providing better corrosion inhibition.

Contributes to research on corrosion protection for copper and its alloys.

The purpose of this paper is to perform the evaluation of copper susceptibility to corrosion in industrial cooling systems. Microstructure and defects of copper are observed, while divergences from optimum structure are discussed.

Various types of corrosion are examined. Electrochemical techniques such as electrochemical impedance spectroscopy and potentiodynamic polarisation are applied in these materials, using corrosion inhibitors. Microscopic observations and electrochemical measurements are interpreted according to possible mechanistic scenarios.

It is evident that, under specific conditions (e.g. high pH), water cooling ingredients can enhance corrosion, leading to significant copper mass loss from the inner surface of the pipe and thus leading to failure.

Evaluation of copper corrosion in cooling industrial systems was done, as well as studies of copper corrosion in sodium chloride.

The purpose of this study was to examine the copper protection against corrosion using 3-thiophenemalonic acid (3TMA).

The heterocyclic organic molecule was tested experimentally as a corrosion inhibitor of copper in two different concentrations (0.01 M and 0.001 M) in 0.5 M solutions of sodium chloride and sulfuric acid by AC electrochemical and DC techniques.

Results showed that the organic compound was adsorbed chemically on the copper surface, and the inhibitions mechanism was both anodic and cathodic. The corrosion mechanism was under mixed control: charge transfer from metal to the environment through the double electrochemical layer, and diffusion processes.

This inhibitor could have application in water cooling systems.

The results of this paper showed that 3TMA could be used for reducing corrosion rates of copper in solutions of sodium chloride and sulfuric acid.

1‐phenyl 5‐mercarpto 1,2,3,4‐tetrazole (PMT) was tested as an inhibitor for the corrosion of steel in 0.5 M H₂SO₄ and 1/3 M H₃PO₄ by weight‐loss and electrochemical methods. Results obtained showed that the inhibition efficiency of PMT increased with the increase of inhibitor concentration and reached an optimum value (98 per cent) at 10⁻³ M in H₂SO₄ and H₃PO₄ solutions. The effect of the temperature on the kinetic parameters of corrosion of steel in the aqueous solutions of H₂SO₄ and H₃PO₄ with and without addition of PMT has been studied and the associated parameters were determined.

This study aims is to evaluate the environmentally friendly turmeric as a corrosion inhibitor for mild steel in a simulated seawater corrosion medium such as a 3.5% NaCl solution. To accomplish this, different proportions of turmeric (0.3, 0.6, 0.9 and 1.5%) were added to solvent-free epoxy-acrylate resin-based coating formulations. Then, all the formulations were sonicated and coated as thin films on different substrates; these coated films were then polymerized under a dose of 10 kGy of electron beam (EB) radiation.

Various properties of all cured coating films such as Fourier transform infrared spectroscopy, water contact angle, thermogravimetric analysis and scanning electron microscopy were studied, in addition to their physical, chemical and mechanical properties. Turmeric was then evaluated in these formulations as an anticorrosion agent for mild steel in 3.5% NaCl. The different corrosion-resistant properties of all EB-cured coating films were evaluated by open circuit potential measurements, rust degree, blistering, adhesion loss at X-cut and weight loss measurements.

The results showed that most of the formulations are homogeneous, especially at low concentrations of turmeric, and their films have high-performance properties.

It was also found that the formulation containing 0.6% of turmeric per 100 g of coating was considered the best formulation as it gave the highest protection to the mild steel plates with no negative effects on the chemical and physical properties of their films.

N-containing heterocyclic benzotriazole derivatives as new corrosion inhibitor for mild steel contained in emulsion were synthesized, and their inhibition behaviors for mild steel (MS) contained in emulsion were investigated by experiments and theoretical calculations, and this study aims to prove that two new inhibitors have excellent inhibition efficiency for steel corrosion.

2-(1H-benzo[d][1,2,3]triazol-1-yl)-N,N-dioctylacetamide (BTN) and O-(3-(1H-benzo[d] [1,2,3]triazol-1-yl)propyl) S-(2-(dioctylamino)-2-oxoethyl) carbonodithioate (BTSC) as a new corrosion inhibitor were synthesized, and their inhibition behaviors for MS contained in emulsion were investigated by gravimetric experiment, electrochemical tests and theoretical calculations.

Results of gravimetric experiment, electrochemical tests show that BTSC exhibit excellent inhibition performance, and it has a higher inhibition efficiency of 96.6% than that BTN. The resultant adsorption films from BTN/BTSC adsorbed on MS, effectively inhibiting the corrosion of MS is mainly through chemisorption and follow to Langmuir’s adsorption isotherm.

Experimental and theoretical calculations display that two new synthesized inhibitors are excellent corrosion inhibitor for MS contained in emulsion. Electrons of inhibitors mainly focus on the C, N, S and O atoms, which demonstrate these atoms are the centers of negative charge, and they supply electrons to Fe atoms through coordination bonds.

The purpose of this paper is to study the effect of vapor assembly sequence and assembly temperature on the corrosion protection of the complex silane films Al alloy. The performance and application range of silane films are enhanced.

The complex silane films were successfully prepared on the surface of aluminum alloy using via vapor phase assembly of 1,2,3-benzotriazole (BTA) and dodecyltrimethoxysilanes (DTMS). The protection of the assembly films against corrosion of Al alloy is investigated by the electrochemical measurements and the alkaline solution accelerated corrosion test. Thickness and hydrophobicity of the complex films are studied using ellipsometric spectroscopy and contact angle tests.

It shows that the anti-corrosion ability of the complex films is overall superior to that of the single-component assembled films. DTMS-BTA films have larger thickness and best anti-corrosion ability. The alkyl chains in DTMS have better compatibility with BTA molecules. The rigid BTA molecule can permeate into the long alkyl chain of DTMS as fillers and improve the barrier properties of the complex films.

In this paper, a green and efficient method of vapor phase assembly is proposed to rust prevention during manufacture of Al alloy workpiece.