Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells

Chou, Y S; Stevenson, Jeffry W

doi:10.1016/j.jpowsour.2009.02.052

Title: Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells

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Abstract

Hybrid phlogopite mica seals with silver interlayers were evaluated in long term isothermal ageing tests in a dual environment consisting of dilute hydrogen vs. air at 800 degrees C. High-temperature leak tests with helium showed very stable leakage of 0.01-0.02 sccm/cm for 28366 hrs under a low applied compressive stress of 82 kPa (12 psi). Post-mortem SEM and EDS analyses of the mica showed minimum degradation in terms of changes in microstructure and chemical composition, although there appeared to be some Ag migration and segregation at interstices between mica flakes. Fluorine was also found to be released from mica. Overall, the low, constant leakage through the hybrid mica/Ag seals clearly demonstrated a very promising candidate for SOFC sealing.

Authors:: Chou, Y S; Stevenson, Jeffry W

Publication Date:: Mon Jun 15 00:00:00 EDT 2009

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 963164

Report Number(s):: PNNL-SA-64433
AA2530000

DOE Contract Number:: AC05-76RL01830

Resource Type:: Journal Article

Journal Name:: Journal of Power Sources, 191(2):384-389

Additional Journal Information:: Journal Name: Journal of Power Sources, 191(2):384-389

Country of Publication:: United States

Language:: English

Citation Formats


                    Chou, Y S, and Stevenson, Jeffry W. Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells.  United States: N. p., 2009. 
        Web.  doi:10.1016/j.jpowsour.2009.02.052.

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                    Chou, Y S, & Stevenson, Jeffry W. Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells.  United States.  https://doi.org/10.1016/j.jpowsour.2009.02.052

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                    Chou, Y S, and Stevenson, Jeffry W. 2009.  
        "Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells".  United States.  https://doi.org/10.1016/j.jpowsour.2009.02.052.

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@article{osti_963164,

  title        = {Long-term ageing and materials degradation of hybrid mica compressive seals for solid oxide fuel cells},

  author       = {Chou, Y S and Stevenson, Jeffry W},

  abstractNote = {Hybrid phlogopite mica seals with silver interlayers were evaluated in long term isothermal ageing tests in a dual environment consisting of dilute hydrogen vs. air at 800 degrees C. High-temperature leak tests with helium showed very stable leakage of 0.01-0.02 sccm/cm for 28366 hrs under a low applied compressive stress of 82 kPa (12 psi). Post-mortem SEM and EDS analyses of the mica showed minimum degradation in terms of changes in microstructure and chemical composition, although there appeared to be some Ag migration and segregation at interstices between mica flakes. Fluorine was also found to be released from mica. Overall, the low, constant leakage through the hybrid mica/Ag seals clearly demonstrated a very promising candidate for SOFC sealing.},

  doi          = {10.1016/j.jpowsour.2009.02.052},

  url          = {https://www.osti.gov/biblio/963164},
  journal      = {Journal of Power Sources, 191(2):384-389},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Mon Jun 15 00:00:00 EDT 2009},

  month        = {Mon Jun 15 00:00:00 EDT 2009}

}

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