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.