What is interfacial corrosion and what types of steel are affected?
Interfacial crevice corrosion is a particular type of failure where silver brazed joints in stainless steel are exposed to water or humidity in service. In these conditions joint failure may result along the stainless steel – brazing filler metal interface. To produce a joint failure by interfacial corrosion three criteria need to be satisfied. 1). At least one member of the joint must be made from a stainless steel. 2). The brazing filler metal must be susceptible to this form of attack. 3). The completed joint must be exposed to damp or wet environments in service. All types of stainless steel are susceptible to attack by interfacial corrosion. The nickel free, or low nickel ferritic and martensitic type stainless steels (e.g. Types 403, 410, 416, 420, 430, 431) are most susceptible to interfacial crevice corrosion. Austenitic grades of stainless steel (e.g. Types 302, 303, 304, 316, 321) are more resistant. Failures with these grades are rare provided the correct brazing alloys are
