BSTO components using Rapid prototyping and different Gelcasting systems
PALLAGANI J. 1, ROSE P. 1, VUMMETHALA S. 1
1 School of Physics, University of Hyderabad, Hyderabad, India
Barium strontium titanate (BSTO) is a technically important material that has piqued the interest of many researchers due to its high dielectric constant, low energy losses, and composition-dependent phase transition temperature [1]. BSTO has perovskite structure and finds application as a high-storage capacitor, tunable filter, sensor, detector, transducer and tunable microwave devices [2]. This paper discusses the synthesis and fabrication of BSTO (Ba0.5Sr0.5TiO3) composites into different shapes and dimensions using environmentally friendly gelling systems like Methyl cellulose when compared to AM (methyl acrylamide) system. BSTO slurry with optimal flow characteristics is prepared and cast into various ABS moulds designed and made using rapid prototyping technique (RPT) [3]. After gelling, the green bodies are dried, debindered and sintered at optimized temperatures. The density of the product is better than 98%. Barium Strontium Titanate rods with lengths of 10 mm and diameters of 3-4 mm are also fabricated. The rods can be assembled into 3D array embedded in a polymer matrix to have a negativise refractive index and create tunable devices with Mie resonance in the microwave frequency range [4 ]. The sintered products are evaluated by measuring densities, microstructures and dielectric properties which are analysed. The current process of fabrication is generic and also allows uniform dispersion of second phase additions, if needed, into the matrix to modify the properties of the composite to suit a chosen application.
References:
[1] A.K. Tagantsev, V.O. Sherman, K.F. Astaev, J. Venkatesh, N. Setter, J. Electroceram. 11, 5–66 (2003)
[2]. Pundareekam Goud, S. Ramakanth, A. Joseph, K. Sandeep, G. Lakshminarayana Rao, K.C. James Raju, Thin Solid Films 626,126–130 (2017)
[3] T. Rajasekharan-1, B. P.M. Sworoop Raju-2, Rakesh Kumar Pandey-3,V Seshu Bai-4, Metals Materials And Processes 2007, 19, No. 1-2, pp. 41-46.
[4] Liang Peng-1, Lixin Ran-2, Jin Au Kong-3, Physical Review Letters 2007,98, 157403.
Acknowledgments:
Facilities procured from a research project funded by DST/TDT/AMT is greatly acknowledged.
This study is supported by facilities from UoH-ACRHEM, UGC-NRC, School of Physics, and University of Hyderabad, India. Funding from DST/TDA/AMT and UGC-JRF for fellowships is acknowledged by PJK and PR respectively.
