Reactive-element-free, silver-based brazes for SOFC applications

Quan Zhou, Thomas R. Bieler, Jason D. Nicholas

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Reactive air Ag-CuO brazes are the most widely used SOFC brazes today. Unfortunately, the high ∼45° wetting angle of the conventional Ag-4 wt.% Cu braze often leads to braze joint manufacturing defects. Furthermore, the reduction of CuO during dual atmosphere (H2/O2) SOFC operation results in pores that: i) mechanically weaken the braze interfaces and ii) provide a shortcircuit path for H2 invasion into the center of the braze (thereby hastening the development of gaseous water pockets formed when oxygen and hydrogen meet within the braze). The present work shows for the first time that porous nickel layers allow high-quality yttria stabilized zirconia-stainless steel braze joints to be produced using reactive-element-free, silver-based brazes. It is expected that the elimination of porosity enabled by this new brazing method will increase SOFC braze joint reliability and lifetime.

Original languageEnglish (US)
Title of host publicationECS Transactions
PublisherElectrochemical Society Inc.
Pages1759-1767
Number of pages9
Volume78
Edition1
ISBN (Electronic)9781607685395
DOIs
StatePublished - May 30 2017
Event15th International Symposium on Solid Oxide Fuel Cells, SOFC 2017 - Hollywood, United States

Other

Other15th International Symposium on Solid Oxide Fuel Cells, SOFC 2017
CountryUnited States
CityHollywood
Period7/23/177/28/17

Profile

Solid oxide fuel cells (SOFC)
Silver
Brazing
Yttria stabilized zirconia
Wetting
Stainless steel
Porosity
Nickel
Protective atmospheres
Hydrogen
Defects
Oxygen
Air
Water

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Zhou, Q., Bieler, T. R., & Nicholas, J. D. (2017). Reactive-element-free, silver-based brazes for SOFC applications. In ECS Transactions (1 ed., Vol. 78, pp. 1759-1767). Electrochemical Society Inc.. DOI: 10.1149/07801.1759ecst

Reactive-element-free, silver-based brazes for SOFC applications. / Zhou, Quan; Bieler, Thomas R.; Nicholas, Jason D.

ECS Transactions. Vol. 78 1. ed. Electrochemical Society Inc., 2017. p. 1759-1767.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Zhou, Q, Bieler, TR & Nicholas, JD 2017, Reactive-element-free, silver-based brazes for SOFC applications. in ECS Transactions. 1 edn, vol. 78, Electrochemical Society Inc., pp. 1759-1767, 15th International Symposium on Solid Oxide Fuel Cells, SOFC 2017, Hollywood, United States, 23-28 July. DOI: 10.1149/07801.1759ecst
Zhou Q, Bieler TR, Nicholas JD. Reactive-element-free, silver-based brazes for SOFC applications. In ECS Transactions. 1 ed. Vol. 78. Electrochemical Society Inc.2017. p. 1759-1767. Available from, DOI: 10.1149/07801.1759ecst

Zhou, Quan; Bieler, Thomas R.; Nicholas, Jason D. / Reactive-element-free, silver-based brazes for SOFC applications.

ECS Transactions. Vol. 78 1. ed. Electrochemical Society Inc., 2017. p. 1759-1767.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

@inbook{8e3cda417f7746789baafc15c45322ef,
title = "Reactive-element-free, silver-based brazes for SOFC applications",
abstract = "Reactive air Ag-CuO brazes are the most widely used SOFC brazes today. Unfortunately, the high ∼45° wetting angle of the conventional Ag-4 wt.% Cu braze often leads to braze joint manufacturing defects. Furthermore, the reduction of CuO during dual atmosphere (H2/O2) SOFC operation results in pores that: i) mechanically weaken the braze interfaces and ii) provide a shortcircuit path for H2 invasion into the center of the braze (thereby hastening the development of gaseous water pockets formed when oxygen and hydrogen meet within the braze). The present work shows for the first time that porous nickel layers allow high-quality yttria stabilized zirconia-stainless steel braze joints to be produced using reactive-element-free, silver-based brazes. It is expected that the elimination of porosity enabled by this new brazing method will increase SOFC braze joint reliability and lifetime.",
author = "Quan Zhou and Bieler, {Thomas R.} and Nicholas, {Jason D.}",
year = "2017",
month = "5",
doi = "10.1149/07801.1759ecst",
volume = "78",
pages = "1759--1767",
booktitle = "ECS Transactions",
publisher = "Electrochemical Society Inc.",
edition = "1",

}

TY - CHAP

T1 - Reactive-element-free, silver-based brazes for SOFC applications

AU - Zhou,Quan

AU - Bieler,Thomas R.

AU - Nicholas,Jason D.

PY - 2017/5/30

Y1 - 2017/5/30

N2 - Reactive air Ag-CuO brazes are the most widely used SOFC brazes today. Unfortunately, the high ∼45° wetting angle of the conventional Ag-4 wt.% Cu braze often leads to braze joint manufacturing defects. Furthermore, the reduction of CuO during dual atmosphere (H2/O2) SOFC operation results in pores that: i) mechanically weaken the braze interfaces and ii) provide a shortcircuit path for H2 invasion into the center of the braze (thereby hastening the development of gaseous water pockets formed when oxygen and hydrogen meet within the braze). The present work shows for the first time that porous nickel layers allow high-quality yttria stabilized zirconia-stainless steel braze joints to be produced using reactive-element-free, silver-based brazes. It is expected that the elimination of porosity enabled by this new brazing method will increase SOFC braze joint reliability and lifetime.

AB - Reactive air Ag-CuO brazes are the most widely used SOFC brazes today. Unfortunately, the high ∼45° wetting angle of the conventional Ag-4 wt.% Cu braze often leads to braze joint manufacturing defects. Furthermore, the reduction of CuO during dual atmosphere (H2/O2) SOFC operation results in pores that: i) mechanically weaken the braze interfaces and ii) provide a shortcircuit path for H2 invasion into the center of the braze (thereby hastening the development of gaseous water pockets formed when oxygen and hydrogen meet within the braze). The present work shows for the first time that porous nickel layers allow high-quality yttria stabilized zirconia-stainless steel braze joints to be produced using reactive-element-free, silver-based brazes. It is expected that the elimination of porosity enabled by this new brazing method will increase SOFC braze joint reliability and lifetime.

UR - http://www.scopus.com/inward/record.url?scp=85028468735&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85028468735&partnerID=8YFLogxK

U2 - 10.1149/07801.1759ecst

DO - 10.1149/07801.1759ecst

M3 - Conference contribution

VL - 78

SP - 1759

EP - 1767

BT - ECS Transactions

PB - Electrochemical Society Inc.

ER -