Effects of 3-D grain boundary geometrical angles and the net normal stress on intergranular stress corrosion cracking initiation in a 316 stainless steel

摘要

The dependence of intergranular stress corrosion cracking (IGSCC) initiation propensity on the grain boundary (GB) characters and geometrical angles was investigated by utilizing a thin sheet 316 stainless steel sample, of which the thickness was approximately equal to the average grain diameter. The low-Sigma CSL GBs especially the Sigma 3 GBs had higher resistance to cracking initiation. The cracking initiation susceptibility (CIS) of a GB increased with the decrease in the GB inclination angle alpha. The net effective normal stress (Delta*sigma(N)) exerted on a GB increased with the Schmid factor mismatch (Delta m) between the two-side grains. It was found that the Delta*sigma(N) initially slightly increased with Delta m when 0 <= Delta m <= 0.04, and then steeply increased with Delta m when 0.04 < Delta m <= 0.18. A criterion was proposed to predict the CIS of a GB, which demonstrated that the CIS of a GB with the Delta*sigma(N) over 0.06 would be high.