Faying Surface Failure
Definition - What does Faying Surface Failure mean?
Faying surfaces failure is a situation in which the contacting surfaces or faces of two similar or dissimilar materials placed next to each other to form a joint either fails to perform the function of a joint or loosens up. In a faying surface failure situation, the sealant between the mated surfaces leaks, which leads to the formation of a gap or crevice between them.
Corrosionpedia explains Faying Surface Failure
Faying surfaces are used to fasten or join two or more members to form a strong structure. To prevent corrosion between the two surfaces, primers or sealing agents are used to provide an air- and moisture-tight joint. In the faying surface failure situation, gaps are created due to primer or sealing agent leakage, which allows air or moisture to enter into the gap. This leaves the inner material open to the corrosion and chemical reactions.
In engineering fabrication and assembly, joints are essential to create intricate structures. However, a poorly installed joint can be a point of failure because they are prone to corrosion. Crevice corrosion, which develops due to gaps between two materials, is commonly encountered in joints. Moisture is the main initiator of any metallic corrosion, so preventing it from becoming trapped between the faying surfaces is a primary consideration when designing joints.