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Effect of hydrogen on the integrity of aluminium-oxide interface at elevated temperatures.

ABSTRACT: Hydrogen can facilitate the detachment of protective oxide layer off metals and alloys. The degradation is usually exacerbated at elevated temperatures in many industrial applications; however, its origin remains poorly understood. Here by heating hydrogenated aluminium inside an environmental transmission electron microscope, we show that hydrogen exposure of just a few minutes can greatly degrade the high temperature integrity of metal-oxide interface. Moreover, there exists a critical temperature of ?150?°C, above which the growth of cavities at the metal-oxide interface reverses to shrinkage, followed by the formation of a few giant cavities. Vacancy supersaturation, activation of a long-range diffusion pathway along the detached interface and the dissociation of hydrogen-vacancy complexes are critical factors affecting this behaviour. These results enrich the understanding of hydrogen-induced interfacial failure at elevated temperatures.

SUBMITTER: Li M

PROVIDER: S-EPMC5321721 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Effect of hydrogen on the integrity of aluminium-oxide interface at elevated temperatures.

Li Meng M Xie De-Gang DG Xie De-Gang DG Ma Evan E Li Ju J Zhang Xi-Xiang XX Shan Zhi-Wei ZW

Nature communications 20170220

Hydrogen can facilitate the detachment of protective oxide layer off metals and alloys. The degradation is usually exacerbated at elevated temperatures in many industrial applications; however, its origin remains poorly understood. Here by heating hydrogenated aluminium inside an environmental transmission electron microscope, we show that hydrogen exposure of just a few minutes can greatly degrade the high temperature integrity of metal-oxide interface. Moreover, there exists a critical tempera ...[more]

PMID: 28218260

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