Electrode Holders for Electrochemical and Electrochemically Controlled Stress Corrosion Experiments at High Temperatures and Pressures

For electrochemical measurements in aqueous solutions at temperatures up to T = 300 C, an electrode holder is necessary which guarantees: (1) complete electrical insulation of the specimen against the autoclave body; (2) a well defined surface area exposed to the electrolyte solution; (3) tight fitting of the specimen in the holder to avoid crevice corrosion at even longer test times, and (4) trouble free, easy and reproducible mounting of the specimen on the fittings.

A few holders for high temperature/high pressure corrosion studies have been described in the literature by Wilde¹  and by

Agrawal, et al.²  This paper describes arrangements which have been shown³  to fulfill all the demands mentioned above properly, both for electrochemical measurements with cylindrical specimens and for potentiostatically controlled stress corrosion experiments with cylindrical tensile specimens at high temperatures in an autoclave.

The assembly for the unstressed cylindrical specimen is shown in...