Investigation of the bonding strength and bonding mechanisms of SOFCs interconnector–electrode interfaces

• SOFC bonding strength is determined by adapted Schwickerath crack initiation test
• The mechanisms of bonding are discussed
• Schwickerath test (ISO9693) applied for the first time to SOFC's interfaces

The determination of the bonding strength (BS) between solid oxide cell (SOC) electrodes and metal interconnects (IC) is of importance since it can impact the SOC lifetime. There are several methods for determining the adhesion between ceramic and metal layers at the macro-scale level, but no standard technique for such measurement is available. In this work, the BSs between an anode support (AS) and three different cathodes with a SOC interconnect were tested in three point bending test configuration. An adaptation of the Schwickerath crack initiation test (SCIT) (ISO 9693) was used to verify its applicability for the determination of bonding strength in the interfaces. The results suggest that this test is a valid method for the mechanical characterization of SOC interfaces.