What is the benefit of using anti-sulfur components?

Anti-Sulfur components are components that employ special finishes on the terminals and/or contacts to help prevent sulfurization. If sulfurization takes place it is possible that an open circuit would occur negatively effecting the circuit. Anti-sulfurization components are suggested for use in sulfur rich environments where the circuit would be more susceptible to sulfurization.

Resistor Sulfuration

Sulfur components exist in a variety of forms in the atmosphere, such as in vehicle exhaust gases and gases emitted from hot springs. These components are adsorbed by metal surfaces, where they will gradually react.

In thick-film chip resistors, sulfur gas in the air can be introduced in the gap between the protective layer and plating, gradually reacting with the internal silver (Ag) electrode to form silver sulfide (Ag2S). (See figure below.) This will cause the internal electrodes to become disconnected, resulting in failure. This failure mode is referred to as disconnection due to sulfide.