In:
CORROSION, Association for Materials Protection and Performance (AMPP), Vol. 75, No. 10 ( 2019-10-01), p. 1237-1245
Abstract:
The presence of hydrogen sulfide (H 2 S) in typical oilfield environments promotes hydrogen absorption and subsequent failure of high-strength steels by sulfide stress cracking (SSC). Plasma nitriding is as a potential method to increase the resistance of the 17-4 PH to SSC, although further investigation is required to evaluate the corrosion resistance of the modified layer when it is exposed to H 2 S-containing environments. The aim of this study was therefore to evaluate the corrosion resistance of the 17-4 PH in typical oilfield environment. Samples were plasma nitrided at low (420°C) and high (500°C) temperatures and immersed in produced water with mixed H 2 S and CO 2 . The electrochemical data and scanning electron microscopy (SEM) micrographs showed that there were no detrimental effects on the corrosion resistance when plasma nitriding was performed at low temperature (420°C), whereas the integrity of the modified layer was compromised when an elevated temperature (500°C) was applied. The enhanced resistance to localized corrosion of the nitride case obtained after the low-temperature surface modification was attributed to the formation of a compound layer of mixed M 4 N/M 2-3 N, the inner section being more corrosion resistant than the outer part, as revealed by SEM micrographs.
Type of Medium:
Online Resource
ISSN:
0010-9312
,
1938-159X
Language:
English
Publisher:
Association for Materials Protection and Performance (AMPP)
Publication Date:
2019
detail.hit.zdb_id:
217266-5
detail.hit.zdb_id:
2043065-6
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