Abstract: The invention is directed to lead-free glass frit compositions that can be used as sealing frits, the compositions being a blend of: (1) at least one of two glass families which are SnO—ZnO—P2O5 and alkali-ZnO—P2O5 glasses; and (2) at least one cerammed filler material having a crystalline phase selected from the group consisting of beta-quartz, beta-eucryptite, cordierite, and beta-spodumene. The blends of the invention have flow characteristics that enable them to be used at sealing temperatures in the range of 450-550° C., and a CTE value in the range of 60-90×10?7/° C.

Abstract: A solid oxide fuel cell device incorporates a sealing material resistant to hydrogen gas permeation at a sealing temperature in the intermediate temperature range of 600° C.–900° C., the seal having a CTE in the 100×10?7/° C. to 120×10?7/° C., wherein the sealing material comprises in weight %, of: (i) a 80 wt % to 100 wt % glass frit, the glass frit itself having a composition comprising in mole percent of: SiO2 15–65; Li2O 0–5; Na2O 0–5; K2O 0–10; MgO 0–5; CaO 0–32; Al2O3 0–10; B2O3 0–50; SrO 0 to 25, wherein the total amount of alkalis is less than 10 mole %; and (ii) zirconia or leucite addition 0 wt % to 30 wt.