{"id":3625,"date":"2026-09-16T11:08:31","date_gmt":"2026-09-16T08:08:31","guid":{"rendered":"https:\/\/www.defencemetal.com\/index.php\/en\/aisi-f55\/"},"modified":"2026-09-25T21:14:54","modified_gmt":"2026-09-25T18:14:54","slug":"aisi-f55","status":"publish","type":"page","link":"https:\/\/www.defencemetal.com\/index.php\/en\/aisi-f55\/","title":{"rendered":"AISI F55 \/ (1.4501)"},"content":{"rendered":"

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AISI F55 \/ (1.4501) \/ UNS S32760<\/h1>\n
DEFENCE METAL<\/span><\/p>\n
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F55 (Zeron 100)<\/div>\n
UNS S32760 \u00b7 W.Nr. 1.4501 \u00b7 X2CrNiMoCuWN25-7-4 \u00b7 in ASTM A240: 24.0-26.0% Cr \u2013 6.0-8.0% Ni \u2013 3.00-4.00% Mo \u2013 0.20-0.30% N \u2013 0.50-1.00% Cu \u2013 0.50-1.00% W \u2013 C \u2264 0.03% \u2013 balance Fe. THIS IS THE ONLY SUPER DUPLEX OF THE FIVE THAT CONTAINS TUNGSTEN, and the W band is binding in the specification. ASTM A240 places a further ACCEPTANCE CRITERION on this row: ‘Cr + 3.3 Mo + 16 N = 40 min.’ \u2014 so PREN \u2265 40 is not a calculated result here but a specification requirement. It is a ferritic-austenitic (super duplex) stainless steel; it is NOT PRECIPITATION HARDENABLE, NOT AGED, and its only heat treatment is solution annealing followed by a quench.<\/p>\n
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Not to be confused with<\/div>\n

AISI F255<\/a>AISI F53<\/a><\/div>\n<\/div>\n<\/div>\n

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For what<\/div>\n
It is bought for seawater and hot chloride service where the PREN has to be guaranteed by the specification: seawater piping systems, offshore production equipment, pump and valve bodies, heat exchangers, sour service equipment.<\/div>\n<\/div>\n
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Forms<\/div>\n
Round bar \u00b7 Flat bar \u00b7 Plate \u00b7 Sheet \u00b7 Pipe and tube \u00b7 Forgings. All forms are supplied to order.<\/div>\n<\/div>\n
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Standards<\/div>\n
THERE IS NO AMS. ASTM: A182 \/ SA-182 \u2014 GRADE F55 (forged flanges and fittings) \u00b7 A240 \/ SA-240 (plate, sheet and strip) \u00b7 A276 \/ SA-276 (bar and shapes) \u00b7 A479 \/ SA-479 (bar and shapes) \u00b7 A789 \/ SA-789 (tube) \u00b7 A790 \/ SA-790 (pipe) \u00b7 A815 \/ SA-815 (wrought fittings) \u00b7 A314 (billets and bars for forging) \u00b7 A473 (forging stock). Rolled Alloys additionally lists A890, A928, A988 and A995. EN: 1.4501 \u00b7 10088-2 \u00b7 10088-3. NORSOK MDS D57 \u00b7 NACE MR0175 \/ ISO 15156 \u00b7 API 6A (Langley Alloys). ASME Section IX welding group P-No 10H (Rolled Alloys, Langley Alloys).
‘F55’ IS a genuine ASTM A182 forging class code, not an alloy name. The duplex class list of ASTM A182 is: F50 = S31200, F51 = S31803, F52 = S32950, F53 = S32750, F54 = S39274, F55 = S32760, F57 = S39277, F59 = S32520, F60 = S32205, F61 = S32550, F65 =\u2026<\/span><\/div>\n<\/div>\n
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Advantage<\/div>\n
It is the only one of the five whose PREN IS GUARANTEED BY THE SPECIFICATION: ASTM A240 places the footnote ‘Cr + 3.3 Mo + 16 N = 40 min.’ on the S32760 row. In the other four grades PREN is a result calculated from the composition and the specification does not make it an acceptance criterion;<\/div>\n<\/div>\n
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Welding<\/div>\n
FILLER METAL: for Zeron 100 the producer specifies its own over-alloyed filler \u2014 Rolled Alloys states ‘ZERON 100 is welded using ZERON 100X filler metal’ and ‘ZERON 100X overalloyed weld filler for welding of ZERON 100 to itself and other stainless steels’.<\/div>\n<\/div>\n
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Limits<\/div>\n
THE TEMPERATURE CEILING is about 300 \u00b0C; the reason is 475 \u00b0C embrittlement. Rolled Alloys gives two different figures in two documents: in the data book ‘not recommended for uses which involve extended exposure to temperatures greater than 572 \u00b0F (300 \u00b0C)’, and in the data sheet ‘greater than 600 \u00b0F as this causes a substantial\u2026<\/div>\n<\/div>\n
REQUEST A QUOTE<\/a>All stainless steels →<\/a>TECHNICAL DETAILS ↓<\/span><\/div>\n
Compiled from manufacturer data sheets \u00b7 confirm against the current specification before ordering<\/div>\n<\/div>\n<\/div>\n

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