J.L. Albarran

Effect of heat treatment on the stress corrosion resistance of a microalloyed pipeline steel

Abstract In this work, the effect of heat treating on a pipeline steel exposed to a sulfide stress cracking (SSC) environment was investigated using LEFM compact specimens. In the as-received condition, specimens with crack orientations parallel and normal to the rolling direction were exposed to H 2 S saturated synthetic sea water at an applied stress intensity ( K I ) of 30 MPa·m 1 2 . In both cases, crack propagation rates were very close to each other (d a /d t =8.77×10 −9 m/s). As the microstructure was modified by heat treating, the rates of crack growth exhibited appreciable differences under similar applied stress intensities. In the martensitic (as-quenched) condition, crack growth was relatively fast (d a /d t =4.72×10 −7 m/s) indicating severe hydrogen embrittlement. In the water sprayed, and in the quenched and tempered conditions, the LEFM specimens exhibited crack arrest events. This, in turn, enabled the determination of threshold stress intensity values ( K ISSC ) for the water sprayed, and for the quenched and tempered conditions of 26 and 32 MPa·m 1 2 , respectively. In addition, favorable paths for microcrack growth were found to be provided by globular inclusions and grain boundary precipitates.

Microstructural Aspects of Sulfide Stress Cracking in an API X-80 Pipeline Steel

AbstractCrack growth in an API X-80 exposed to sour gas environments was investigated using modified wedge-opening-loaded (MWOL) specimens. The MWOL specimens were tested in the as-received condition and after annealing followed by water spraying to simulate improperly welded regions. It was found that water-sprayed MWOL specimens were susceptible to stress sulfide cracking in a NaCl-free NACE solution. Crack growth was relatively slow when subjected to an initially appliedKI of 30 MPa

The Sour Gas Susceptibility of an X-80 Steel for Oil and Gas Transport

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Crack growth in a welded microalloyed steel under sulfide stress cracking conditions

. Under these conditions, crack growth rates continually decreased until crack arrest was exhibited at a thresholdKI (KISSC) of 26 MPa

Properties of reinforced glass with crystalline particles

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The role of heat treating on the sour gas resistance of an X-80 steel for oil and gas transport

. The exhibited crack growth rates were related to the facility with which nucleated microcracks joined the main crack front. Apparently, preferential nucleation and growth of microcracks within the main crack tip plastic zone accounted for the exhibited embrittlement. In particular, favorable microcrack growth followed a path consisting of fractured (cut) carbide regions, as well as various interfaces, including globular inclusions and grain boundary precipitates.