2015 Volume 64 Issue 7 Pages 311-314
The objective in this study was to clarify the effect of electrodeposited Ca film on hydrogen entry behavior into API-X65 by measurements of hydrogen content and an electrochemical hydrogen permeation technique in Ca(OH)2 and NaOH solutions under constant current cathodic hydrogen charging. As a result, hydrogen content in the steel cathodically charged in Ca(OH)2 solution was larger than that in NaOH solution, which was attributed to the formation of Ca film. And hydrogen permeation efficiency on the area where electrodeposited Ca film didn't exist (reaction part) was measured by the electrochemical hydrogen permeation technique. From 0 to 40% of electrodeposited Ca film coverage, it was clarified that hydrogen permeation efficiency increased and hydrogen entry was enhanced at the reaction part. It was clarified that hydrogen permeation efficiency decreased and hydrogen entry was inhibited at the reaction part when the electrodeposited Ca film coverage was more than 40%.
