The long-term performance of a solid oxide fuel cell is very dependent on the materials and techniques used to hermetically seal the components of the stack. Researchers at PNNL have developed a method for fabricating durable and thermal-mechanically stable seals for solid oxide fuel cells (SOFC) needing metal-to-metal or metal-to-ceramic joining.

Known as the Gas-Tight Sealing Method, the technique employs a surface modification or coating that creates an optimum surface for the seal. Aluminum is applied to the metal component surface and oxidized to form Al2O3 or an oxide film embedded with nodules is thermally grown on the surface of metal substrate. The surface modification changes the surface chemistry and morphology of the metal allowing for better compatibility with other metal parts and sealing materials. The nodules embedded in the metal bonding surface that provides for better adhesion to a sealing layer of glass, metal or a combination of materials.