Study on Stress Corrosion Cracking of Austenitic Stainless Steels (Report 3)

Eeffects of Stress and Potential on Initiation of Crack

Abstract

In the report 2, the processes of stress corrosion cracking for 18 Cr-8 Ni stainless stainless steel and its welded metal were analyzed by the method of continuous observation with microscope. Then it became cleare that the processes could be divided into two parts : "Induction period" and "Propagation period" and the lengthes of these two periods were change independently each other by the variation of stress.
In this report, we investigated above two processes of stress corrosion cracking of six kinds of austenitic stainless steels and welded metal from the points of electrochemical study and the continuous observation of the cracks by microscope.
Main results of our experiment are as follows:
1) There is a linear relation between the corrosion potential and the value of applied stress when a crack initiates.
2) The above relation can be observed in every kinds of austenitic stainless steels.