Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
3 results
Search Results
Item Influence of Chloride Content and Exposure Time on Corrosion Behavior of AZ80 Wrought Mg Alloy(Springer Nature, 2020) Gote, G.D.; Naik, G.M.; Narendranath, S.This study aims to investigate the corrosion behavior of wrought AZ80 magnesium alloys in different chloride ion concentrations and exposure time. During the study, the effect of exposure time and chloride content on the corrosion resistance of AZ80 wrought Mg alloy has been studied with 2, 3.5, and 5 wt% NaCl aqueous solution for 12 h and 24 h exposure time. Charge transfer resistance for each sample was established using the Nyquist plot and corrosion rate obtained from polarization curve by adopting Tafel extrapolation method. Corrosion morphology was examined using scanning electron microscopy and XRD. The study revealed that corrosion product layer formed at initial stage was observed unstable after short exposure time which results in decrease in corrosion resistance at initial stage. An increase of chloride content in aqueous environment reduces the corrosion resistance of AZ80 wrought Mg alloy. © 2020, Springer Nature Singapore Pte Ltd.Item Complex impedance spectroscopy properties of Fe3BO6 nanocrystallites prepared by combustion method(Elsevier Ltd, 2019) Kumari, K.; Ramteke, R.; Rahman, M.R.In this investigation, we report a part of our work on Impedance spectroscopy of Fe3BO6 nanoceramics prepared by a selfcombustion of a solid precursor mixture of 60Fe2O3-40B2O3 using camphor as a fuel in ambient air. A single phase compound Fe3BO6 of an orthorhombic crystal structure with Pnma space group and average crystallites size D = 42 nm is analyzed from the X-ray diffractogram. The Z?-value decreases with a shift in the peak frequency towards the higher side with rise in temperature arises possibly due to the presence of dipolar response in the material, which is in good agreement with the observation of complex impedance data. Temperature dependent impedance describes Fe3BO6 to be an ionic conductor; with activation energy (Ea) value0.73 eV. The Ea-values so obtained for the dielectric relaxation from the tp-values suggests a conduction mechanism involving the polaron hopping. © 2019 Elsevier Ltd. All rights reserved.Item Modeling and experimental studies on the dynamics of bolted joint structure: Comparison of three vibration-based techniques for structural health monitoring(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2020) Deka, A.; Rao, A.; Kamath, S.; Gaurav, A.; Gangadharan, K.V.Detection of inadequate tightening in bolted joints is quintessential to ensure structural rigidity and to prevent catastrophic failure. Studies show that 30% of assembly failures occur due to inadequate tightening. In the present study, three vibration-based techniques are presented and compared to detect inadequate tightening of bolted joints. Variation in the damped natural frequency, variation in the damping ratio, and variation in the dynamic joint stiffness are studied with varying tightening torques in the bolted joint. The results show that all the three dynamic parameters vary with the tightness of the bolted joint. Dynamic joint stiffness varies significantly as opposed to the damping ratio and damped natural frequency as tightening torque reduces. In order to verify the results of dynamic stiffness method, ANSYS is used to model and analyze the joint. The experimental setup used to calculate the parameters consists of two Euler–Bernoulli beams connected with single lap bolted joint. © Springer Nature Singapore Pte Ltd 2020.