Morphology and Properties of Zn-Al-TiO2 Composite on Mild Steel

The influence of TiO2 composite and dispersed pure Al particle on zinc alloy electrodeposited on mild steel was studied from chloride bath solution.Microstructural and mechanical properties of the alloy were investigated. The structure, surface morphology, and surface topography of the deposited alloys were characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM).In addition, hardness of the coated alloys was measured. It was found that the obtained Zn-Al-TiO2 alloyexhibited more preferred surface morphology and mechanical strength compared tothe substrate. The result shows the existence of interaction between TiO2 compounds and zinc alloy particulate. It also exhibited well bright dominate zinc coating on steel surface

Electrochemical Potential Monitoring of Corrosion and Inhibitors Protection of Mild Steel Embedded in Concrete in NaCl Solution

The corrosion and protection behaviour of mild steel embedded in concrete, and partially immersed in 3.5% sodium chloride solution, was studied in this investigation at ambient temperature by potential monitoring technique. The work was performed with a digital multimeter and a Cu/CuSO4 electrode (CSE) as the reference electrode. Extracts of pawpaw (carica papaya) leaves and sodium nitrite in different concentrations were separately and in combination, used as inhibitors. This paper reports the observed electrochemical response from the electrode potential monitoring of the embedded mild steel during the experiments. The results obtained, showed a reduction in the active corrosion reactions behaviour of the embedded mild steel in concrete admixed with different concentrations of sodium nitrite and the pawpaw leaves extracts thus indicating corrosion inhibition characteristic. The observed inhibition was attributed to the protective film provided on the steel’s surface in the concrete by the complex chemical compounds of the plant leaves’ extracts and the reaction of sodium nitrite with the alkaline environment of the concrete and its constituents. The combination of pawpaw extracts and the NaNO2 solution provided effective corrosion inhibition of the embedded steel by synergism. The 100% concentration of each of the inhibitors and when in combinations, exhibited the most effective corrosion inhibition performanc

Effect of Anode and Size Variations on the Cathodic Protection of Mild Steel in Sea Water and Sulphuric Acid

The performance of different sizes of zinc, and aluminium galvanic anodes on the cathodic protection of mild steel in seawater and 0.2 M sulphuric acid was evaluated at ambient temperature. The magnitude of corrosion protection by the galvanic anodes was observed by weight loss method,corrosion rate calculation and potential measurement technique. It was observed that the aluminium anodes proved more effective as sacrificial anode for mild steel in seawater environment. In sulphuric acid environment, the zinc anode gave a more protective performance than aluminium anode. Potential measurement results obtained were found to correspond with the results obtained from weight loss method. For both environments, the effects of a varying cross-sectional area and the anode material on the cathodic protection of mild steel were examine

Effect of Tobacco and Kola Tree Extracts on the Corrosion Inhibition of Mild Steel in Acid Chloride

Corrosion and inhibitor protection of mild steel specimens immersed in acid chloride solution was investigated at ambient temperature by gravimetric and potential monitoring methods. The electrode potential monitoring was performed using a digital voltmeter and a saturated calomel electrode (SCE) as the reference electrode. Extracts of kola plant and tobacco in different concentrations were used as ‘green’ inhibitors. This paper reports the results obtained from the weight loss method, calculated corrosion rates and the observed electrochemical response from the electrochemical potential monitoring of the mild steel during the experiments. A reduction in the active corrosion reactions behaviour of the mild steel test specimens in the strong acid chloride was obtained with the addition of different concentrations of the plants extracts. There was a drastic reduction in the weight loss and in the corrosion rate of the test samples. This behaviour was attributed to the protective film provided on the steel’s surface by the complex chemical constituents of the plants extracts. Effective protection of the mild steel was achieved in nearly all the extracts for the greater part of the experimental period. However, the most effective results were obtained from the tobacco extract and also from the extract of kola leaf

Environmental Surface Degradation of Galvanised and Mild Steels in Cattle and Poultry Wastes and Urea Solution

An investigation of the corrosive properties of cattle and poultry dung/urine slurries and urea solution and by extension, the corrosion resistance of galvanised and mild steels in these respective test media was performed by the weight loss method. The results showed corrosive surface degradation of galvanised steel and extensive corrosion of the mild steel test specimens by the corrosive constituents of the various test media. The corrosive constituents in the slurries are believed to be urea, uric acid,ammonia and ammonium salts, naturally excreted chloride (common salt), carbon-dioxide and sulphate reducing and sulphur oxidizing bacteria. The galvanised steel is found to be more corrosion resistant than the mild steel. The cattle dung/urine slurry was found to be the most aggressive of the test media and the poultry dung/urine slurry, the least corrosive medium

PLANTS EXTRACTS CORROSION INHIBITION OF ALUMINIUM ALLOY IN H2SO4

Effects of tobacco (Nicotiana) and Kola tree (Cola acuminata) extracts on the corrosion inhibition of an aluminium alloy 2S (1200) grade specimens immersed in 0.5M sulphuric acid was investigated at ambient temperature by gravimetric and metallographic methods. Extracts of kola plant and tobacco in different concentrations were used as ‘green’ inhibitors. This paper reports the results obtained from the weight loss method, calculated corrosion rates, inhibitor efficiencies and the optical microscopy metallographic observations. Addition of different concentrations of the plants extracts gave clear reduction in weight loss and in the corrosion rate of the test samples. This apparent corrosion inhibition was associated with the protective film provided on the aluminium alloy’s surface by the complex chemical constituents of the plants extracts

Effect of Cola Acuminata and Camellia Sinensis Mixed Extracts on the Corrosion Inhibition of Mild Steel in 0.5M Sulphuric Acid

The corrosion inhibition effect of extracts of kola plant (cola acuminata) and green tea (camellia sinensis) in mixed form on the protection of mild steel specimens immersed in sulphuric acid solution was studied at ambient temperature by gravimetric and potential monitoring methods. The electrode potential monitoring was performed using a digital voltmeter and a saturated calomel electrode (SCE) as the reference electrode. Extracts of kola plant and green tea in different concentrations and combinations were used as ‘green’ inhibitors. There was significant reduction in the weight loss and in the corrosion rate of the test samples, particularly at the added extracts concentration of 100% and also at the concentrations of 50 and 25%. Some very good inhibitor efficiency values were obtained which suggested good corrosion inhibition performance of the added extracts at the concentrations used. Potential measurement values recorded showed a reduction in active corrosion reactions for all the combinations of the extracts. This behavior was attributed to the protective film provided on the steel’s surface by the complex chemical constituents of the plants extracts. The best corrosion inhibition performance for mild steel was obtained using the combined extracts of kola leaf and green tea at100% concentration. The combination of kola leaf, kola nut and green tea at the same concentration was also effective in corrosion inhibition performanc

Inhibition Effect of Kola Tree and Tobacco Extracts on the Corrosion of Austenitic Stainless Steel in Acid Chloride Environment

Corrosion and inhibitor protection of austenitic stainless steel (Type 304) specimens immersed in acid chloride solution was investigated at ambient temperature by weight loss method from which the corrosion rates were calculated and inhibition efficiency determined. Extracts of kola plant; the nut, bark and leaf and tobacco leaf in different concentrations were used as ‘green’ inhibitors. This paper reports the results obtained from the various tests performed in the acid chloride environment on the stainless steel during the experiments. The addition of different concentrations of the plants extracts gave some reduction in the active corrosion reactions behavior of the steel specimen in the strong acid chloride. There was a reduction in the weight loss and in the corrosion rate of the test samples, though not very significant. The stainless steel was self-passivated; the passive film was, however, significantly destroyed by the strong reacting species of the test solution. The reduction in weight loss was attributed to the protective film provided on the steel’s surface by the complex chemical constituents of the plants extracts. Effective protection of the austenitic stainless steel was minimally achieved in nearly all the extracts for the greater part of the experimental perio

Inhibitive effect of ferrous gluconate on the electrochemical corrosion of aluminium alloy in H2SO4 solution

The use of ferrous gluconate as corrosion inhibitor on aluminium alloy in 0.5M H2SO4 solution was studied using gravimetric and potentiodynamic polarization measurements. The surface morphology of the aluminium alloy was studied after exposure to 0.5 M H2SO4 solution in the presence and absence of inhibitor using high resolution scanning electron microscopy equipped with energy dispersive spectroscopy (HRSEM – EDS). The adsorption behaviour of the inhibitor was investigated. The results of the investigation show that increase in concentration of ferrous gluconate corresponds to an improvement on inhibition efficiency. Equally, the results showed the ferrous gluconate to be an effective corrosion inhibitor for the aluminium in the acidic medium. The results obtained from the two methods used were found to correlate with each other

Effect of Saccharum officinarum Juice Extract Additive on the Electrodeposition of Zinc on Mild Steel in Acid Chloride Solution

Experimental investigations have been performed to examine the electrodeposition of zinc on mild steel in acid chloride solution using as additive different concentrations of saccharum officinarum (sugarcane) juice extracts. The experiments were performed under different plating time, different additive concentrations and fixed pH conditions. Zinc electrodeposition on mild steel was performed using a DC – supply at defined operating parameters. The surface of the plated steel was examined using scanning electron microscopy (SEM); and Energy Dispersive Spectroscopy (EDS) for surface elemental composition analysis. Different surface characteristics were obtained depending upon the concentration of the additive and the plating time. The corrosion resistance of the plated surface was also determined by gravimetric method. The quality of electrodeposition of zinc was good as indicated by the plated surface microstructural morpholog