Cadmium-Rich Reaction Products Can Interrupt Low-Level Relay Contacts

What the evidence preview establishes

Failed contacts contained a carbon-, oxygen-, and cadmium-rich surface product. The combined electrical, imaging, and chemical evidence supported accumulation of a nonconductive reaction product on Ag-CdO contacts rather than mechanical binding.

Why this case matters

Contact chemistry, housing outgassing, contact material, and switching current must be evaluated together. Detecting contamination is only the beginning; the useful question is whether its composition, location, and electrical behavior form a consistent failure mechanism.