Alloy 31, a new 6 moly stainless steel with improved corrosion resistance in seawater
- Krupp VDM GmbH, Werdohl (Germany)
Alloy 31--UNS N08031--31Ni-27Cr-6.5Mo-1.2Cu-0.2N-balance iron--is an advanced 6 Mo stainless steel with increased chromium and nickel, contents for seawater service. In hot seawater the pitting potential of alloy 31 remains high up to 90 C (194 F). Investigations of resistance to crevice corrosion in real piping systems in natural seawater, both North Sea and Baltic Sea, show that the threshold conditions for alloy 31 in chlorinated seawater (North Sea) are at 40 C and 1 ppm chlorine well superior to the 6 Mo stainless grades being currently in use. In addition, alloy 31 shows an excellent resistance to corrosion versus both hot reducing media (e.g. H{sub 2}SO{sub 4}) and hot oxidizing media (e.g. HNO{sub 3}). The combination of high resistance to localized corrosion vs. hot chloride-bearing cooling waters including seawater and aggressive oxidizing and reducing hot corrosive media is a unique feature of alloy 31. Alloy 31 is recommended for the construction of heat exchangers, process coolers and piping systems. The material is supplied in a number of semifinished products such as seamless and welded pipes, fittings, flanges, forged bars, plate, sheet, strip, wire and prefabricated piping systems.
- OSTI ID:
- 109945
- Report Number(s):
- CONF-950304-; TRN: IM9543%%246
- Resource Relation:
- Conference: Corrosion `95: National Association of Corrosion Engineers (NACE) international annual conference and corrosion show, Orlando, FL (United States), 26-31 Mar 1995; Other Information: PBD: 1995; Related Information: Is Part Of Corrosion/95 conference papers; PB: 5788 p.
- Country of Publication:
- United States
- Language:
- English
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