A stress-corrosion-cracked type-304 austenitic stainless steel was investigated by the Doppler broadening of annihilation radiation spectroscopy with a positron microbeam. Clear increase of S parameter was observed over 200-400μm areas from the stress corrosion cracking crack. From the comparison of the Doppler broadening of annihilation radiation spectra obtained from the stress-corrosion-cracked sample and plastically deformed sample, the increase of S parameter around the stress corrosion crack was attributed to plastic-deformation-induced vacancies.

Positron Microbeam Study on Vacancy Generation Caused by Stress Corrosion Crack Propagation in Austenitic Stainless Steels. A.Yabuuchi, M.Maekawa, A.Kawasuso: Journal of Physics - Conference Series, 2011, 262[1], 012067