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Oxygen Transport Ceramic Membranes Quarterly Report

Description: This report covers the following tasks: Task 1--Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints; Task 2--Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability; Task 3--Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres; Task 4--Evaluate phase stability and thermal expansion of candidate perovskite membranes and devel… more
Date: April 1, 2002
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
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Oxygen Transport Ceramic Membranes Quarterly Report

Description: In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Processing of perovskites of LSC, LSF and LSCF composition for evaluation of mechanical properties as a function of environment are begun. The studies are to be in parallel with LSFCO composition to characterize the segregation of cations and slow crack growth in environmental conditions. La{sub 1-x}Sr{sub x}FeO{sub 3-d} has also be… more
Date: January 1, 2003
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: Conversion of natural gas to liquid fuels and chemicals is a major goal for the Nation as it enters the 21st Century. Technically robust and economically viable processes are needed to capture the value of the vast reserves of natural gas on Alaska's North Slope, and wean the Nation from dependence on foreign petroleum sources. Technologies that are emerging to fulfill this need are all based syngas as an intermediate. Syngas (a mixture of hydrogen and carbon monoxide) is a fundamental building… more
Date: January 1, 2002
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: This is the fourth quarterly report on a new study to develop a ceramic membrane/metal joint. The first experiments using the La-Sr-Fe-O ceramic are reported. Some of the analysis performed on the samples obtained are commented upon. A set of experiments to characterize the mechanical strength and thermal fatigue properties of the joints has been designed and begun. Finite element models of joints used to model residual stresses are described.
Date: July 1, 2000
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: In the present quarter, oxygen transport perovskite ceramic membranes are evaluated for strength and fracture in oxygen gradient conditions. Oxygen gradients are created in tubular membranes by insulating the inner surface from the reducing environment by platinum foils. Fracture in these test conditions is observed to have a gradient in trans and inter-granular fracture as opposed to pure trans-granular fracture observed in homogeneous conditions. Fracture gradients are reasoned to be due to o… more
Date: July 1, 2002
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: The mechanical properties of model systems were analyzed. A reasonably accurate finite element model was implemented and a rational metric to predict the strength of ceramic/metal concentrical joints was developed. The mode of failure of the ceramic/metal joints was determined and the importance of the mechanical properties of the braze material was assessed. Thermal cycling experiments were performed on the model systems and the results were discussed. Additionally, experiments using the conce… more
Date: July 1, 2001
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: The mechanical properties of model systems were analyzed. A reasonably accurate finite element model was implemented and a rational metric to predict the strength of ceramic/metal concentrical joints was developed. The mode of failure of the ceramic/metal joints was determined and the importance of the mechanical properties of the braze material was assessed. Thermal cycling experiments were performed on the model systems and the results were discussed. Additionally, experiments using the conce… more
Date: May 1, 2001
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: In the present quarter, the possibility of using a more complex interfacial engineering approach to the development of reliable and stable oxygen transport perovskite ceramic membranes/metal seals is discussed. Experiments are presented and ceramic/metal interactions are characterized. Crack growth and fracture toughness of the membrane in the reducing conditions are also discussed. Future work regarding this approach is proposed are evaluated for strength and fracture in oxygen gradient condit… more
Date: January 1, 2003
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect co… more
Date: October 1, 2000
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
open access

Oxygen Transport Ceramic Membranes Quarterly Report

Description: This is the fifth quarterly report on a new study to develop a ceramic membrane/metal joint. Results of wetting experiments on commercially available Nickel based brazing alloys on perovskite surfaces are described. Additionally, experimental and numerical investigations on the strength of concentric ceramic/metal joints are presented.
Date: February 1, 2001
Creator: Bandopadhyay, Sukumar & Nagabhushana, Nagendra
Partner: UNT Libraries Government Documents Department
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