Prabhakar Kuppahalli, Ramaiah Keshavamurthy, Padmanathan Sriram, Ahobal Narayana,
Volume 18, Issue 2 (June 2021)
Abstract
The present investigation aims to synthesize RB031, RB032 manganese bronze alloys equivalent to HTB1 and HTB2 alloys with additions of silicon and to characterize them with the help of Microstructure and Mechanical properties. The methodology involves melting of alloy’s in a 300kg Coreless medium frequency induction furnace, casting them in Permanent and Shell moulds with optimum values of Zinc equivalent and retaining their high mechanical properties. The study includes the development and mechanical property measurements of the alloys synthesized. Characterization has been carried out using Optical Microscopy and Scanning Electron Microscopy with EDAX analysis for investiagtion of compositional variations and inquisition of hardness measurement & tensile properties. It is concluded from this work that RB032 alloy cast in Permanent moulds has superior hardness and tensile properties compared to Shell moulds and far exceeds that of NAB (AB2) alloys processed under similar conditions. Further, this investigation includes grain refinement by suitable Heat treatment studies to combat Hot Tearing since the strength is adequate enough with RB032 exhibiting higher hardness than other two alloys.
M Suganya, C Kayathiri, Ar Balu, G Vinitha, Z Delci, S Chitra Devi, K Devendran, M Sriramraj,
Volume 21, Issue 0 (IN PRESS 2024)
Abstract
Perovskite materials are widely studied for their super-conducting, magnetic, catalytic and electro-optic properties. Among them, barium stannate (BaSnO3), finds applications in dielectric and optically active devices, thermally stable capacitors, humidity and gas sensors. In this study, BaSnO3 was synthesized by chemical and greener methods and comparative analyses has been performed on their electrochemical, third order nonlinear, dye deactivation and bacterial suppression properties. Decreased crystallite size was realized for the green synthesized BaSnO3. Energy band gaps were 3.23 and 3.04 eV for BaSnO3 synthesized by normal and greener approach, respectively. The extract mediated sample exhibited increased specific capacitance value. Photocatalytic degradation efficiencies were 78.4% and 89.7%, respectively for BaSnO3 synthesized by normal and greener approach against methyl violet after 90 min of UV light irradiation. Enhanced nonlinear optical parameters were obtained for the extract mediated BaSnO3. Excellent antibacterial efficacy against Proteus vulgaris bacteria was realized for the greener BaSnO3 NPs thanks to the domination of phytochemicals of M. olifera leaf extract.