Trends in wetting behavior for Ag–CuO braze alloys on Ba_0.5Sr_0.5Co_0.8Fe_0.2O_(3-δ) at elevated temperatures in air

Journal Article · Fri Jun 21 04:00:00 EDT 2013 · Journal of Materials Science

DOI:https://doi.org/10.1007/s10853-013-7531-2· OSTI ID:1091452

Joshi, Vineet V.; Meier, Alan; Darsell, Jens; Weil, K. Scott; Bowden, Mark

Ba_0.5Sr_0.5Co_0.80.2O_(3-δ)(BSCF) is a potential oxygen separation membrane material for advanced coal based power plants. For this application, BSCF must be joined to a metal. In the current study, Ag-CuO, a reactive air brazing (RAB) alloy was evaluated for brazing BSCF. In-situ contact angle tests were performed on BSCF using Ag-CuO binary mixtures at 950 and 1000°C and the interfacial microstructures were evaluated. Wetting contact angles (θ< 90°) were obtained at short times at 950°C and the contact angles remained constant at 1000°C for 1, 2 and 8 mol% CuO contents. Microstructural analysis revealed the dissolution of copper oxide into the BSCF matrix to form copper-cobalt-oxygen rich dissolution products along the BSCF grain boundary. The formation of a thick interfacial reaction product layer and ridging at the sessile drop triple point indicate that the reaction kinetics are very rapid and that it will require careful process control to obtain the desired thin but continuous interfacial product layer.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1091452
• Report Number(s): PNNL-SA--94525; 38191; AA6010000
• Journal Information: Journal of Materials Science, Journal Name: Journal of Materials Science Journal Issue: 20 Vol. 48; ISSN 0022-2461
• Publisher: Springer
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Ag-CuO
BSCF
Brazing
Environmental Molecular Sciences Laboratory
Reactive Air Brazing
Wetting