Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
The nucleating, growing and cracking of hydrogen blister have been investigated experimentally and theoretically. The results show that atomic hydrogen induces superabundant vacancies in metals. The superabundant vacancies and hydrogen aggregate into a hydrogen-vacancy cluster (microcavity). The hydrogen atoms in the microcavity become hydrogen molecules which can stabilize the cluster. And the hydrogen blister nucleates. With the entry of vacancies and hydrogen atoms, the blister nucleus grows and the pressure in the cavity increases. When the stress induced by hydrogen pressure on the blister is up to the cohesive strength, cracks will initiate from the wall of the blister.hydrogen blister, vacancy cluster, nucleation, cracking Hydrogen blister or hydrogen crack appears in many materials in the absence of external stress when the hydrogen concentration is high enough [1][2][3] . The mechanisms of the formation of the blisters or cracks have been discussed widely [4][5][6] . Most of the mechanisms suggest that hydrogen atoms combine into hydrogen molecules in the interface of second phase and matrix, and the hydrogen molecules produce high hydrogen pressure to induce microcracks. The propagation and connection of the microcracks induce the formation of the hydrogen blisters or hydrogen cracks. Hydrogen atoms cannot combine into hydrogen molecules which induce hydrogen pressure when there is no interspace to accommodate the hydrogen atoms. Hydrogen atoms can be trapped in pre-existing microvoids or microcracks in a material and become hydrogen molecules. The microvoids or microcracks containing hydrogen molecules become hydrogen blisters (a lacuna full of H 2 in the interior of materials also is called a hydrogen blister in this paper). For some materials with good plasticity and even single crystalline metals, there are neither microvoids nor microcracks in them, but hydrogen blisters or hydrogen cracks can appear if they are charged. How are the lacunas containing H 2 (hydrogen blister) produced?There are abundant supersaturated vacancies in metals quenched from high temperature. The supersaturated vacancies can aggregate into vacancy clusters (microlacuna) and then collapse into dislocation loops or stacking fault tetrahedral [7] . If the supersaturated vacancies can be induced by hydrogen and can aggregate into vacancy clusters to accommodate molecular hydrogen, the hydrogen blisters will be formed during charging. This work is an attempt to confirm this hypothesis through experiments and theoretical analysis. Here a mechanism describing the nucleating, growing and cracking of hydrogen blister in metals is presented.
The nucleating, growing and cracking of hydrogen blister have been investigated experimentally and theoretically. The results show that atomic hydrogen induces superabundant vacancies in metals. The superabundant vacancies and hydrogen aggregate into a hydrogen-vacancy cluster (microcavity). The hydrogen atoms in the microcavity become hydrogen molecules which can stabilize the cluster. And the hydrogen blister nucleates. With the entry of vacancies and hydrogen atoms, the blister nucleus grows and the pressure in the cavity increases. When the stress induced by hydrogen pressure on the blister is up to the cohesive strength, cracks will initiate from the wall of the blister.hydrogen blister, vacancy cluster, nucleation, cracking Hydrogen blister or hydrogen crack appears in many materials in the absence of external stress when the hydrogen concentration is high enough [1][2][3] . The mechanisms of the formation of the blisters or cracks have been discussed widely [4][5][6] . Most of the mechanisms suggest that hydrogen atoms combine into hydrogen molecules in the interface of second phase and matrix, and the hydrogen molecules produce high hydrogen pressure to induce microcracks. The propagation and connection of the microcracks induce the formation of the hydrogen blisters or hydrogen cracks. Hydrogen atoms cannot combine into hydrogen molecules which induce hydrogen pressure when there is no interspace to accommodate the hydrogen atoms. Hydrogen atoms can be trapped in pre-existing microvoids or microcracks in a material and become hydrogen molecules. The microvoids or microcracks containing hydrogen molecules become hydrogen blisters (a lacuna full of H 2 in the interior of materials also is called a hydrogen blister in this paper). For some materials with good plasticity and even single crystalline metals, there are neither microvoids nor microcracks in them, but hydrogen blisters or hydrogen cracks can appear if they are charged. How are the lacunas containing H 2 (hydrogen blister) produced?There are abundant supersaturated vacancies in metals quenched from high temperature. The supersaturated vacancies can aggregate into vacancy clusters (microlacuna) and then collapse into dislocation loops or stacking fault tetrahedral [7] . If the supersaturated vacancies can be induced by hydrogen and can aggregate into vacancy clusters to accommodate molecular hydrogen, the hydrogen blisters will be formed during charging. This work is an attempt to confirm this hypothesis through experiments and theoretical analysis. Here a mechanism describing the nucleating, growing and cracking of hydrogen blister in metals is presented.
A zirconia sol was prepared by the sol-gel method and coated on the surface of stainless steel substrates. The gas corrosion test was carried out for the stainless steel substrates and for the coated samples using a high-temperature and high-pressure reactor. The coated samples and the substrates were placed in the reaction kettle, and it was filled with the H 2 S gas at the pressures of 0.6, 0.8, and 1 MPa. After standing at room temperature for 24 h, the samples were observed by optical microscopy and a scanning electron microscopy, and it was found that as the pressure increases, the corrosion of the stainless steel substrates are more severe, while the film samples show only slight pitting corrosion. The experimental results show that in the corrosive H 2 S gas environment, the stainless steel samples coated with the ZrO 2 film can effectively block the H 2 S gas corrosion on the stainless steel substrate and reduce the hydrogen bubbling and hydrogen-induced cracking caused by gas corrosion. This finding has important practical significance for improving the service life of oil pipelines and reducing the occurrence of oil spills and other accidents.
The effect of element sulphur on the performance of corrosion inhibitor in H 2 S/CO 2 gas field solution was investigated at different velocities. The morphology and composition of corrosion products were characterised by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) methods. The results indicated that L360 QS steel surface suffered from sulphur-induced pitting corrosion at a low velocity due to insufficient sulphur-carrying fluid power. At high flow velocities, the steel surface is likely to be suffered high fluid power which can remove the inhibitor film and corrosion scales by the mechanical erosion effect. The sulphur corrosion mechanism model and the flow-induced corrosion model due to the high wall shear force have been proposed in the study. This work suggested that the gas production rate should be controlled at an acceptable level to guarantee the service safety of pipeline system.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.