Corrosion characteristics of the iron-aluminum alloy layer and the welding zone of aluminum-coated steel in hydrogen sulfide

Journal Article · Wed Mar 01 04:00:00 EST 1995 · Corrosion

DOI:https://doi.org/10.5006/1.3294366· OSTI ID:28027

Yajiang, L; Yonglan, Z ^[1]

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1. Shandong Polytechnic Univ., Jinan (China). Materials Engineering Dept.

Practical experience in processing sour crude oil, especially highly sour crude oil, has shown that H{sub 2}S can promote serious corrosion in oil refinery equipment exposed to high temperatures and may result in hydrogen embrittlement (HE) and H{sub 2}S stress corrosion cracking, seriously threatening normal operation. Phase constitution of the iron (Fe)-aluminum (Al) alloy layer and corrosion behavior of the welding zone of Al-coated steel in saturated hydrogen sulfide (H{sub 2}) solution were studied using a metalloscope, scanning electron microscope, and X-ray diffractometer. H{sub 2}S was generated by reacting sulfuric acid solution and saturated sodium sulfide solution. The Fe-Al alloy layer was composed mainly of {delta}-Fe(Al) solid solution, Fe{sub 3}Al and FeAl. There were no brittle FeAl{sub 2}, Fe{sub 2}Al{sub 5}, or FeAl{sub 3} phases in the Fe-Al alloy layer. Pitting attack occurred in the Fe-Al alloy layer in the heat-affected zone (HAZ), while electrochemical attack was concentrated in the fusion zone.

• Sponsoring Organization: USDOE
• OSTI ID: 28027
• Journal Information: Corrosion, Journal Name: Corrosion Journal Issue: 3 Vol. 51; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
36 MATERIALS SCIENCE
ALUMINIUM
ALUMINIUM ALLOYS
CORROSION
CORROSIVE EFFECTS
ELECTROCHEMICAL CORROSION
HYDROGEN SULFIDES
INTERMETALLIC COMPOUNDS
IRON ALLOYS
PETROLEUM REFINERIES
PHASE STUDIES
PIPES
PITTING CORROSION
STEELS
WELDED JOINTS