Faculty Publications
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Item Investigation of influence of medium ph and sulfate ion concentrations on corrosion behavior of magnesium alloy ZE41(Allerton Press Inc., 2014) Dinodi, N.; Nityananda Shetty, A.Magnesium alloys have emerged as potential structural materials with all capabilities to even replace close contenders; aluminium alloys in weight-critical applications. High susceptibility to corrosion being the only limitation, corrosion of magnesium alloys continues to gather much attention among the material scientists worldwide. ZE41 is one such alloy of magnesium which is increasingly gaining importance as automobile and aerospace material. In the present study the influence of the medium pH and sulfate ion concentrations on the corrosion behavior of magnesium alloy ZE41 has been investigated using electrochemical techniques like the Tafel extrapolation and electrochemical impedance spectroscopy (EIS). The tests have been carried out in a range of conditions, with gradually varying pH and sulfate ion concentration. The morphology and composition of the corroded alloy surface have been determined by the scanning electron microscopy (SEM) and energy dispersion X-ray (EDX) analysis, respectively. The recorded results reflect a trend of a higher corrosion rate associated with a higher sulfate concentration at each pH and with a lower pH at each sulfate concentration. © 2014 Allerton Press, Inc.Item Alkyl carboxylates as efficient and green inhibitors of magnesium alloy ze41 corrosion in aqueous salt solution(Elsevier Ltd, 2014) Dinodi, N.; Nityananda Shetty, A.Long chain alkyl carboxylates like stearate, palmitate and myristate were investigated for their efficiency in inhibiting the corrosion of magnesium alloy ZE41 in an aqueous salt medium containing 0.2M Na2SO4 and 0.1M NaCl. The techniques like potentiodynamic polarization and EIS, along with SEM and EDX analyses were employed. The inhibition was proposed to be the result of adsorption of alkyl carboxylates, which was found to obey the Langmuir adsorption isotherm. The inhibition was assumed to be the outcome of the formation of a compact modified surface film due to the precipitation of adsorbed alkyl carboxylates of magnesium. © 2014 Elsevier Ltd.Item Corrosion behavior of 6061/Al-15 vol. pct. SiC(p) composite and the base alloy in sodium hydroxide solution(Elsevier B.V., 2016) Reena Kumari, P.D.; Nayak, J.; Nityananda Shetty, A.The corrosion behavior of 6061/Al-15 vol. pct. SiC(p) composite and 6061 Al base alloy was investigated in a sodium hydroxide solution. The electrochemical parameters were derived from potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The results showed that the corrosion resistance of the composite was lower than that of the base alloy in selected corrosion media. The corrosion rates of both the composite and the base alloy increased with the increase in the concentration of sodium hydroxide and also with the increase in temperature. The surface morphology of the metal surface was investigated using scanning electron microscope (SEM). Activation energy was evaluated using Arrhenius equation, and enthalpy of activation and entropy of activation values were calculated using transition state equation. © 2012Item 2-(4-(Diethylamino)-2-hydroxybenzyledene) Hydrazinecarboamide as Corrosion Inhibitor on AA2024-T3 Aluminium Alloy in 0.5 M Hydrochloric Acid Solution(Pleiades Publishing compmg@maik.ru, 2018) Prakashaiah, B.G.; Nityananda Shetty, A.; Amitharani, B.E.A new compound 2-(4-(diethylamino)-2-hydroxybenzyledene) hydrazinecarboamide (DHBHC) was prepared by the condensation of thiosemicarbazide and diethylaminosalicyaldehyde in ethanol–water mixture and its purity was confirmed with IR, H1 and C13 NMR. Anticorrosion properties of this new compound were studied on the aluminium alloy AA2024-T3 in 0.5M HCl solution at 303 K by potentiodynamic polarization, electrochemical impedance spectroscopy and weight loss method. The inhibition efficiency of DHBHC was found to increase with an increase of its concentration. The inhibition efficiency obtained in this study was 96 ± 3% in the presence of 10 × 10?5 M of DHBHC. The surface morphology of the alloy was investigated both in the presence and in the absence of the inhibitor by field emission scanning electron microscopy, 3D profilometry and X-ray photoelectron spectroscopy. © 2018, Allerton Press, Inc.