LAUSR

Hydrogen-induced cracking (HIC) is one of the major issues of line pipe exposed to sour environments. There are some guidelines on materials requirements for carbon and low alloy steels for H2S-containing environments in oil and gas production. Generally, HIC susceptibility is evaluated after the test duration, typically 96 h, in accordance with NACE Standard TM0284-2016. However, HIC propagation behavior during HIC test has not been fully understood. In this study, a new in situ HIC measurement method has been developed in order to make the connection between HIC propagation behavior and microstructure. This technique is based on the combination of an automatic ultrasonic wave inspection system and a scanning electron microscopy (SEM) observation. HIC propagation rate and HIC propagation behavior of carbon steels with different textures were investigated, using this in situ technique. Texture components of tested steels were changed by controlled rolling process in the alpha-gamma dual phase region. The ...