Influence of aging on intergranular corrosion of a 25% chromium-5% nickel duplex stainless steel

Journal Article · Fri Apr 01 00:00:00 EST 1994 · Corrosion (Houston); (United States)

DOI:https://doi.org/10.5006/1.3294339· OSTI ID:7198654

Ravindranath, K; Malhotra, S N ^[1]

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1. Indian Inst. of Tech., Bombay (India). Dept. of Metallurgical Engineering

Although duplex stainless steels (SS) exhibit good performance in many severe corrosive environments, their corrosion resistance can be hampered by precipitation of chromium (Cr)- and molybdenum (Mo)-rich phases during heat treatments. The influence of aging treatments on intergranular corrosion (IGC) of a commercial 25% Cr-5% nickel (Ni) duplex SS (UNS S32550) was studied. The SS was given aging treatments in the range 773 K to 1,173 K for durations from 6 min to 100 h. Microstructure study of the aged samples indicated the presence of various phases, among them [sigma], Cr-rich carbide, secondary austenite, [alpha][prime], and copper (Cu)-rich precipitate. The influence of these precipitated phases on IGC susceptibility of the SS was evaluated by the ferric sulfate (Fe[SO[sub 4]][sub 3])-sulfuric acid (H[sub 2]SO[sub 4]) and Cu-copper sulfate-(CuSO[sub 4])-H[sub 2]SO[sub 4] tests. Results indicated [sigma]- and Cr-rich carbide increased IGC susceptibility greatly, as did aging in the range 873 K to 1,073 K.

• OSTI ID: 7198654
• Journal Information: Corrosion (Houston); (United States), Vol. 50:4; ISSN 0010-9312
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM-NICKEL STEELS
AGING
INTERGRANULAR CORROSION
PETROCHEMICAL PLANTS
PETROLEUM REFINERIES
PHASE STUDIES
UNDERWATER FACILITIES
ALLOYS
CHEMICAL PLANTS
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CORROSION
HIGH ALLOY STEELS
INDUSTRIAL PLANTS
IRON ALLOYS
IRON BASE ALLOYS
NICKEL ALLOYS
STAINLESS STEELS
STEELS
360105* - Metals & Alloys- Corrosion & Erosion
360101 - Metals & Alloys- Preparation & Fabrication