Hydrogen-Assisted Crack Growth in the Heat-Affected Zone of X80 Steels during in Situ Hydrogen Charging

Abstract

Herein, the hydrogen embrittlement of a heat-affected zone (HAZ) was examined using slow strain rate tension in situ hydrogen charging. The influence of hydrogen on the crack path of the HAZ sample surfaces was determined using electron back scatter diffraction analysis. The hydrogen embrittlement susceptibility of the base metal and the HAZ samples increased with increasing current density. The HAZ samples have lower resistance to hydrogen embrittlement than the base metal samples in the same current density. Brittle circumferential cracks located at the HAZ sample surfaces were perpendicular to the loading direction, and the crack propagation path indicated that five or more cracks may join together to form a longer crack. The fracture morphologies were found to be a mixture of intergranular and transgranular fractures. Hydrogen blisters were observed on the HAZ sample surfaces after conducting tensile tests at a current density of 40 mA/cm2, leading to a fracture in the elastic deformation stage.

Hydrogen-induced cracking and corrosion behavior of friction stir welded plates of API 5L X70 pipeline steel

“…The material flow at the advanced side around the tool undergoes highly severe plastic deformation and thermal exposure because of the lower frictional forces. The advanced side peak temperature was slightly higher than that at the retreating side [65,66], possibly created by the hard zone.…”

“…In the rolling direction, in Figure 6a The type, density, and distribution of non-metallic inclusions and the segregation bands greatly impacted HSLA steel performance in the H 2 S environment. Also, the segregation region is the most preferred area for HIC crack propagation [65,66]. When examining the path and crack propagation, irregular inclusions were found.…”

Hydrogen-Assisted Cracking in GMA Welding of High-Strength Structural Steel—A New Look into This Issue at Narrow Groove

“…For investigation of hydrogen embrittlement, different test methods exist. Tests regarding the influence of diffusible hydrogen on degradation of different microstructures and steels are mainly carried out on electrochemically hydrogen charged tensile specimens [28][29][30][31]. When it comes to welding, there are numerous self-restraint and externally loaded test procedures for investigating HAC [32,33].…”