Stress Corrosion Cracking Testing in SCW - Results of SSRT Tests

Abstract

The presented paper summarizes the results of stress corrosion cracking (SCC) susceptibility tests in supercritical water (SCW), studied for austenitic alloys 316L, 316NG, 347HP and Alloy 690 with the aim to identify maximum SCW temperature usability and specific failure mechanisms prevailing during slow strain-rate tensile (SSRT) tests in ultra-pure demineralized SCW solution with controlled oxygen content. Besides the strain rate (resp. crosshead speed), the oxygen content was varied in the series of tests in case of austenitic stainless steel 316L. The fractography confirmed that failure was due to a combination of transgranular SCC and transgranular ductile fracture. Based on fractographic findings a phenomenological map describing the SCC regime of SSRT test parameters could be proposed for AISI 316L.JRC.DDG.F.4-Safety of future nuclear reactor