アコースティック・エミッションと電位揺動の同時計測による進展性塩化物応力腐食割れのモニタリング
Monitoring of Chloride Stress Corrosion Cracking utilizing Simultaneous Measurement of Acoustic Emission and Corrosion Potential Fluctuation
著者:
米津 明生 Akio YONEZU 長 秀雄 Hideo CHO 竹本 幹男 Mikio TAKEMOTO
発刊日:
公開日:
Acoustic EmissionChloride Stress Corrosion CrackingCorrosion potential monitoringMonitoring Technique
概要
This paper discusses monitoring method of active path corrosion (anodic dissolution ) type SCC of stainless steel utilizing both of acoustic emission (AE) and corrosion potential fluctuation (CPF). The SCC in this paper is limited t o chloride SCC of Type-304 steel. TG-SCC in boiling 42% MgCl2 solution (JIS ???) does not emit strong AEs since it is caused by anodic dissolution of active path. However we often monitor weak AEs from fracture of corrosion products, friction of SCC and hydrogen gas evolution. These AEs are classified as secondary AES .Contrary to the TG-SCC, we detect the strong AEs from IG-SCC. These AES were classified as primary AEs and produced by falling-off of grains and successfully utilized of progressive SCC monitoring. The RD-type CPF, caused by non-faradic reaction of transient anodic current, can be utilized for detection of SCC susceptibility or initiation but not be used for SCC progression.
