Monitoring of Stress Corrosion Cracking in Type 304 Stainless Steel under the High Temperature and the High Pressure Water Environment Using Optical Fiber Acoustic Emission Sensor

Abstract

Stress Corrosion Cracking (SCC) in stainless steel specimens under a high temperature and a high pressure water environment was monitored in the Crevice Bent Beam (CBB) test using an optical fiber AE sensor. Type 304 stainless steel was monitored during 294 ks under 513 K and 4.0 MPa, respectively. 5227 AE signals were detected. AE event rate was increased after 155 ks from start of the experiment. AE signals were extracted using AE waveforms and their frequency spectra in all time. 4 AE signals were extracted. Those AE were estimated to be occurred by large cracks that occurred after 155ks.