Effects of solid loading on joining and thermal cycling performance of glass-ceramic sealing pastes for solid oxide fuel cells


Timurkutluk B., Celik S. , Ucar E.

Ceramics International, vol.45, no.10, pp.12845-12850, 2019 (Journal Indexed in SCI Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 45 Issue: 10
  • Publication Date: 2019
  • Doi Number: 10.1016/j.ceramint.2019.03.207
  • Title of Journal : Ceramics International
  • Page Numbers: pp.12845-12850
  • Keywords: Glass-ceramics, Sealing, Solid loading, Solid oxide fuel cell, Tensile tests, Thermal cycling

Abstract

© 2019 Elsevier Ltd and Techna Group S.r.l.The variation of the joining performance of glass-ceramic sealants in the form of a paste as a function of the solid powder content in the sealing paste after the formation and a number of thermal cycles are experimentally studied. Three different sealing pastes having 40, 50 and 60 wt % solid loadings are prepared and tested for this purpose. The pastes are applied between two metallic interconnector plates and subjected to a glass formation step for the joining. The fracture strengths of 24 samples prepared for each case are determined via tensile tests. Similarly, the mechanical performances of the sealants after 3, 6 and 9 thermal cycles are also obtained. The results reveal that the joining strength tends to increase with the amount of solid powder content in the paste. This can be attributed to increased number of crystalline phases in the sealants with increasing the solid loading. The thermal cycles, on the other hand, are shown to have an adverse effect on the joining performance regardless of the solid loading. However, the rate of decrease in the fracture strengths is found to decrease with the solid powder contents in the pastes. This can be elucidated by the amount of glassy phases in the sealants, which can be expected to increase with the solid loading and provide self-healing ability. The microstructures of the fracture surfaces of all samples are also investigated by a scanning electron microscopy. The obtained images confirm the tensile test results.