Study of the Reactivity of Silver,Copper,Silver-Copper, and Silver-Palladium Alloys used in Telephone Relay Contacts

A study is presented of the contamination of pure silver and copper as well as silver-copper and silver-palladium alloys which are used in telephone relay contacts. The contamination tests have been conducted in mixtures of synthetic air + H
2
O + H
2
S, with various H
2
O and H
2
S concentrations. The amount of resulting contamination on the samples has been determined mainly by electrochemical reduction. With the help of the Centre National d'Etudes des Télécommunications (CNET), France,it was possible to determine the nature and quantity of the contamination deposited on telephone contacts of various compositions having performed under controlled atmospheres.