ADVANCED CORROSION RESISTANT NICKEL-ALLOYS FOR MARINE APPLICATIONS, INCLUDING CRYOGENIC SERVICE

摘要

HASTELLOY® alloys C-86® and C-22HS® are presently being used or evaluated by the Navy bolting applications where both high strength, toughness, ductility, resistance to corrosion and hydrogen embrittlement are required. Alloys C-86 and C-22HS have been used in severe applications that require both corrosion resistance and high strength and C-22HS has properties applicable to cryogenic service. The C-22HS alloy is included in NACE MR0175/ISO 15156 exhibiting resistance to extremely severe corrosive environments. Properties of these alloys relevant to marine corrosion and Navy fastener applications are presented. The C-22HS alloy yield strength ranges from 191 to 205 ksi (1317 to 1413 MPa). The C-22HS alloy also displays excellent ductility and fracture toughness of ≥150 ft-lbs (≥203 J) from -300℉ to +550℉ (-149 to 288°C). Superior corrosion resistance, high yield strength, low magnetic permeability and outstanding cryogenic properties define the C-22HS alloy's usefulness. NITRONIC® 50HS (UNS S20910) Stainless Steel provides a combination of corrosion resistance and strength not found in any other commercial material available in its price range. As a result, the use of this alloy for boat shafting is significantly increasing for commercial and naval shipping. NITRONIC 50HS is currently used by the USCG for shafting on the Fast Response Cutter.