Sonia Mago

Bio: Sonia Mago is an academic researcher from Punjab Technical University. The author has contributed to research in topics: Cubic zirconia & Yttria-stabilized zirconia. The author has an hindex of 5, co-authored 9 publications receiving 40 citations.

The Influence of Various Dopants and Sintering Techniques on the Properties of the Yttria-Ceria-Zirconia System As an Electrolyte for Solid Oxide Fuel Cells

Abstract: Zirconia-based ceramic oxides Zr0.90Y0.06Ce0.02X0.02O2−δ (X = Ca, Fe, La, Sr, and Mg) were prepared by conventional and microwave processing. The precursors of Zr0.90Y0.06Ce0.02X0.02O2−δ (X = Ca, Fe, La, Sr, and Mg) were prepared by a mixed oxide method and were calcined at 600°C in an electric furnace. The powders were consolidated in pellet form and sintered in a conventional electric furnace at 1400°C for 6 h and compared using microwave energy at 1400°C for 20 min. The structure and microstructure of sintered products obtained by both methods were studied by x-ray diffraction and scanning electron microscopy. Their density and microhardness were also compared. The electrical conductivities of these samples were studied using alternating current impedance spectroscopy. The analysis of the products obtained by microwave aand conventional methods shows that the microwave sintered samples have uniform grain growth, higher density, higher microhardness and higher electrical conductivity than the corresponding conventionally sintered products. The microwave sintered sample of composition Zr0.90Y0.06Ce0.02Ca0.02O2−δ was found to have the highest density and microhardness, as well as the highest electrical conductivity among all of the microwave and conventionally sintered products.

Comparative Analysis of Yttria Stabilized Zirconia (YSZ) and Titania Doped YSZ (YZT) Sintered by two Different Routes: Conventional and Microwave Processing

Abstract: Besides YSZ (yttria stabilized zirconia) as an appropriate anode material, YZT (titania doped YSZ) is emerging as a material of interest. The undoped YSZ and the doped YSZ i.e. 5 mol % YZT, are synthesized by conventional as well as microwave processing techniques, from the precursors prepared by mixed oxide method and subsequently characterized for a comparative analysis by XRD, Raman spectroscopy, FTIR, SEM and Vickers hardness test to investigate the crystal structure, structural changes taking place during the processing, the surface morphology and the micro hardness of sintered products. Whereas earlier, others have processed the same compositions conventionally, in the present investigation, microwave energy has been exploited for sintering YZT composites. Notable density, phase stabilization, grain growth, hardness and density are observed for microwave sintered products.

Effect of Microwave Sintering on the Properties of Zirconia Based Ceramic Electrolytes for Solid Oxide Fuel Cells

Abstract: In this work, the effect of microwave sintering on the properties of scandia doped zirconia (10 mol% scandia in zirconia) was investigated. The sample was prepared by mixed oxide method and the sin...

Fuel cell materials and components

Abstract: Fuel cells offer the possibility of zero-emissions electricity generation and increased energy security. We review here the current status of solid oxide (SOFC) and polymer electrolyte membrane (PEMFC) fuel cells. Such solid electrolyte systems obviate the need to contain corrosive liquids and are thus preferred by many developers over alkali, phosphoric acid or molten carbonate fuel cells. Dramatic improvements in power densities have been achieved in both SOFC and PEMFC systems through reduction of the electrolyte thickness and architectural control of the composite electrodes. Current efforts are aimed at reducing SOFC costs by lowering operating temperatures to 500–800 °C, and reducing PEMFC system complexity be developing ‘water-free’ membranes which can also be operated at temperatures slightly above 100 °C.

Effect of titania addition on yttria-stabilised tetragonalzirconia ceramics sintered at high temperatures

Abstract: In order to combine the mechanical properties of yttria-stabilised zirconia (ZrO2–3 mol% Y2O3; code Y–ZrO2) with the bioactivity of titania (TiO2), Y–ZrO2–TiO2 green compacts with 0–40 vol.% TiO2 were sintered at 1300, 1400, and 1500 degrees Celsius for 4 h, respectively. The microstructural features such as grains, pores, and phases were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDX). The mechanical properties such as hardness and toughness were also determined using the methods of Vickers indentation and Knoop indentation. All the composites showed the major tetragonal Y–ZrO2 phase regardless of the content of the added TiO2. However, rutile TiO2 phase was obtained at 1300 degrees Celsius, whereas zirconium titanate (ZrTiO4) phase was found at 1400 and 1500 degrees Celsius. The Y–ZrO2–ZrTiO4 composites sintered at 1500 degrees Celsius showed relatively high hardness (860–1000 kg/mm2) and toughness(4.0–4.5MPam0.5), whereas the Y–ZrO2–TiO2 composites sintered at 1300 degrees Celsius had slightly lower hardness (720–950 kg/mm2) and fracture toughness (3.1–3.3MPam0.5).

Effect of Lanthanum Zirconate on High Temperature Resistance of Thermal Barrier Coatings

Abstract: Thermal barrier coatings (TBCs) typically have low thermal conductivity and high resistance to oxidation at elevated temperatures. TBCs are used to protect the turbine blades of aircraft engines op...