Sintering Behavior and Phase Characterisation of Composite Perovskite/Fluorite Ceramics for Intermediate Temperature SOFCs and Oxygen Separation Membranes

AbstractThe sintering behavior and structural changes of fluorite Gd0.2Ce0.8O2-δ(GDC) with one of three perovskites: LaMnO3 (LMO), (La0.7Sr0.3)0.98MnO3 (LSM) and La0.6Sr0.4Fe0.8Co0.2O3 (LSFC) composite ceramics were studied. Sintering was carried out for two hours at five different temperatures: 1100°C, 1200°C, 1300°C, 1400°C, and 1500°C. The highest sinterability has been found in LSFC + GDC. LSM + GDC appear to undergo two-step sintering mechanisms. Of all types of ceramics, only sintered LMO experiences a phase change, from rhombohedral R C to orthorhombic Pnma structure, with respect to its powder phase at sintering temperatures ≥1200 °C. The transition is notably suppressed when LMO is part of an LMO + GDC composite. GDC in a fluorite and/perovskite composite, when sintered, undergoes a temperature-dependent expansion in its unit cell that is not observed in pure GDC ceramics. This structural change will impact the function of composite ceramics as a fuel cell cathode, or oxygen separation membranes.

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Design and Characterization of LSM-ScCeSZ Nanocomposite as MIEC Material for SOFC Cathode and Oxygen-separation Membranes

10.1557/proc-1126-s13-03 ◽

2008 ◽

Author(s):

Vladislav A. Sadykov ◽

Vitalii Muzykantov ◽

Aleksei Bovin ◽

Lubsan Batuev ◽

Galina Alikina ◽

...

Keyword(s):

Oxygen Separation ◽

Sofc Cathode ◽

Separation Membranes

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Heat Treatment Influence on the Corrosion Resistance of a Cu-Al-Fe-Mn Bronze

Revista de Chimie ◽

10.37358/rc.18.5.6260 ◽

2018 ◽

Vol 69 (5) ◽

pp. 1055-1059 ◽

Cited By ~ 1

Author(s):

Mariana Ciurdas ◽

Ioana Arina Gherghescu ◽

Sorin Ciuca ◽

Alina Daniela Necsulescu ◽

Cosmin Cotrut ◽

...

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Structural Changes ◽

Heating Temperature ◽

Galvanic Corrosion ◽

Cooling Water ◽

Open Circuit ◽

Water Quenching ◽

Heat Treated ◽

Different Temperatures

Aluminium bronzes are exhibiting good corrosion resistance in saline environments combined with high mechanical properties. Their corrosion resistance is obviously confered by the alloy chemical composition, but it can also be improved by heat treatment structural changes. In the present paper, five Cu-Al-Fe-Mn bronze samples were subjected to annealing heat treatments with furnace cooling, water quenching and water quenching followed by tempering at three different temperatures: 200, 400 and 550�C. The heating temperature on annealing and quenching was 900�C. The structure of the heat treated samples was studied by optical and scanning electron microscopy. Subsequently, the five samples were submitted to corrosion tests. The best resistance to galvanic corrosion was showed by the quenched sample, but it can be said that all samples are characterized by close values of open-circuit potentials and corrosion potentials. Concerning the susceptibility to other types of corrosion (selective leaching, pitting, crevice corrosion), the best corrosion resistant structure consists of a solid solution, g2 and k compounds, corresponding to the quenched and 550�C tempered sample.

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Global Sensitivity Analysis on Temperature-Dependent Parameters of A Reduced-Order Electrochemical Model And Robust State-of-Charge Estimation at Different Temperatures

Energy ◽

10.1016/j.energy.2021.120024 ◽

2021 ◽

Vol 223 ◽

pp. 120024

Author(s):

Guodong Fan ◽

Xiaoyu Li ◽

Ruigang Zhang

Keyword(s):

Sensitivity Analysis ◽

Global Sensitivity Analysis ◽

State Of Charge ◽

Temperature Dependent ◽

Reduced Order ◽

Global Sensitivity ◽

Different Temperatures ◽

Electrochemical Model ◽

State Of Charge Estimation

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Preparation and Characterization of NTC NiMn2O4-La1-xCaxMnO3 (0≤x≤0.3) Composite Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.716.78 ◽

2013 ◽

Vol 716 ◽

pp. 78-83 ◽

Cited By ~ 1

Author(s):

Hui Min Zhang ◽

Fang Guan ◽

Ai Min Chang ◽

Li Jun Zhao

Keyword(s):

Electrical Resistivity ◽

Perovskite Structure ◽

Spinel Structure ◽

Thermal Constant ◽

Inrush Current ◽

Composite Ceramics ◽

Sem Images ◽

Conventional Solid State Reaction ◽

Different Temperatures ◽

Xrd Patterns

Composite ceramics made of spinel structure NiMn2O4 and CaO-doped perovskite structure LaMnO3 were prepared by a conventional solid state reaction and sintered at different temperatures. The XRD patterns have shown that the major phases presented in the sintered samples are NiMn2O4 compounds with the spinel structure, La1-xCaxMnO3 with the perovskite structure and NiO with a monoclinic structure. SEM images show that the density and grain size of the composite ceramics increases with sintered temperature increasing. The electrical resistivity of the composite ceramics at 25°C is found to change significantly depending on the CaO content, while the thermal constant B is still reasonably large in the range of 2400 to 3000 K. For the composition x = 0.1, the composite with a low electrical resistivity (ρ25°C=4.46Ω·cm) and moderate B value (B25/50=2762K) was obtained. These composites could be applied as potential candidates for NTC thermistors in the suppression of the inrush current.

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