In-situ observation and acoustic emission analysis for scc of mgcl2 droplet in sus304 stainless steel

Abstract

Acoustic emission and optical video microscope monitoring was proposed to investigate the stress corrosion cracking of work-hardened SUS304 stainless steel caused by a small magnesium-chloride droplet. The crack propagation length could measure clearly under the droplet by VMS. The SCC started at 4582 ks with pitting. The crack velocity was 3.24.7μm/ ks and it propagated almost continuously. AE signals were generated at early stage of SCC testing of 55 and 82 ks, after that they were generated discontinuously. With the SEM observations, the detected AE signals were mainly attributed to cracking of the oxidation products and discontinuous crack propagation at the falling-off surface grain. © 2014 The Japan Institute of Metals and Materials.