Shear Performance at Room and High Temperatures of Glass⁻Ceramic Sealants for Solid Oxide Electrolysis Cell Technology

To provide a reliable integration of components within a solid oxide electrolysis cell stack, it is fundamental to evaluate the mechanical properties of the glass⁻ceramic sealing materials, as well as the stability of the metal⁻glass⁻ceramic interface. In this work, the mechanical behavior of two previously developed glass⁻ceramic sealants joined to Crofer22APU steel is investigated at room temperature, 650 °C, and 850 °C under shear load. The mechanical properties of both the glass⁻ceramics showed temperature dependence. The shear strength of Crofer22APU/glass⁻ceramic/Crofer22APU joints ranged from 14.1 MPa (20 °C) to 1.8 MPa (850 °C). The elastic modulus of both glass⁻ceramics also reduced with temperature. The volume fraction of the crystalline phases in the glass⁻ceramics was the key factor for controlling the mechanical properties and fracture, especially above the glass-transition temperature.