2007 Volume 56 Issue 6 Pages 265-271
The corrosion of silver when exposed to sulfur vapor was studied in a tubular vessel and a boxy vessel. The sulfur vapor released from sulfur flower reacted with the silver plate in the tubular vessel and the silver electrode of the corrosion sensor in the boxy vessel. The thickness of the corrosion product on silver plate was measured using a cathodic reduction method, and that on silver electrode was measured using a resistometry. After exposure, silver sulfide that had formed on the silver plate and silver electrode was analyzed. When sulfur vapor is released from sulfur flower, diffusion of the sulfur vapor is the main factor limiting the rate of silver corrosion. The silver corrosion rate when exposed to sulfur vapor released from sulfur flower was estimated using a diffusion network model that calculated the corrosion reaction. Sulfur vapor reacts with silver at a constant rate corresponding to a reaction probability of 3×10−5. This estimation technique is useful for verifying the effectiveness of countermeasures and can be used to ensure the equipment's reliability.