Chlorides induced stress corrosion cracking (ESCC) behavior was examined for SUS304L, SUS316L and SUS304 stainless steels (SS) after depositing synthetic sea water simulating sea salt particles at a temperature range from 333 K to 353 K with relative humidity of 35%. A stress-ESCC failure time relationship was formulated for SUS304L SS as σ=-
Alog(
tf)+
B, where σ : applied stress (MPa),
tf : time to failure (h),
A=23.7
T-7020,
B=43.7
T-11600,
T : absolute temperature (K). Even an incipient micro-crack was not observed on the specimen surface of the SS at the applied stress level of 0.25σ
y (σ
y : 0.2% proof stress), although SCC initiated at the applied stress level of 0.5σ
y. Thus the threshold stress should be between 0.5σ
y and 0.25σ
y for these SS, and the threshold stress would rise beyond these values if the stress concentration be considered at the bottom and circumference of a pit. A statistical analysis suggested that the ESCC crack length and crack depth conformed to the double exponential distribution.
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