Barium-aluminosilicate-based seals

Many barium aluminosilicate-based compositions will eventually react with the chromium oxide or aluminum oxide scales on the metal interconnect or metal edge rails to form barium chromate or a celsian phase at the interface [6], This can cause a mechanical weakness that is easily delaminated. Also, compositions that contain boron can react over time with water (steam) to produce B2(OH)2 or B(OH)3 gas. This can decompose the glass and greatly limit the lifetime of the seal. Thus many of the new investigations have emphasized low or no boron glass compositions. 

Z.G. Yang, K.S. Weil, K.D. Meinhardt, J.W. Stevenson, D.M. Paxton, G.-G. Xia, and D.-S. Kim, Chemical compatibility of barium-calcium-aluminosilicate base sealing glasses with heat resistant alloys, in Joining of Advanced and Speciality Materials... 

Z. Yang et al., Chemical Compatibility of Barium-Calcium-Aluminosilicate-Based Sealing Glasses with the Ferritic Stainless Steel Interconnect in SOFCs, Journal of the Electrochemical Society, 150(8), pp. A1095-A1101 (2003). 

Z. Yang, J.W. Stevenson, and K.D. Meinhardt, Chemical interactions of barium-calcium-aluminosilicate-based sealing glasses with oxidation resistant alloys. Solid State Ionics, 160 (2003) 213-225. 

Chemical compatibility of barium-calcium-aluminosilicate-based sealing glasses with the ferritic stainless steel interconnect in SOFCs. J. Electrochem. Soc., 150, A1095-A1101. 

In addition to the aforementioned interactions with the surrounding gas environments, metallic interconnects also interact with adjacent components at their interfaces, potentially causing degradation of metallic interconnects and affecting the stability of the interfaces. One typical example is the rigid glass-ceramic seals, in particular those made from barium-calcium-aluminosilicate (BCAS) base glasses [205-209], FSS interconnect candidates have been shown to react extensively with... 

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