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254 SMO A182 F44 904L — material overview

Looking for a valve in this exotic alloy? Find it in the following configurations: Ball, Butterfly, Cast, Check, Control, Cryogenic, Custom made, Foot, Forged, Gate, Globe, Needle, Plug, and Safety relief, as well as Strainers.

Alloy Valve Stockist supplies 254 SMO, A182 F44 and 904L gate, globe, check, ball, butterfly, plug, needle and custom made valves.

Principal Design Features

This is a very high end austenitic stainless steel that combines impact toughness resistance to chloride stress corrosion cracking, pitting and crevice corrosion with strength nearly twice that of 300 series stainless steels. In some applications it has been found to be a more cost effective substitute for high nickel and titanium alloys.


Petroleum production, saltwater handling, food processing and chemical processing equipment, pulp mill bleach systems, flue gas desulfurization scrubbers and tall oil distillation columns.


ASTM A182 (F44), ASTM A240, ASTM A249, ASTM A269, ASTM A312, ASTM A469, ASTM A813, ASTM A814, UNS S31254, 6 Moly.


An extremely high work hardening rate combined with a total lack of sulfur make 254-SMO very tough to machine. Sharp tools, positive feeds, overpowered machine tools, ample lubrication and slow speeds generally offer the best results.


Due to its high initial yield strength, this alloy will require greater force than used in other austenitic stainless steels.


Welding without filler material results in poor strength properties. Recommended filler metals include AWS A5.14 ERNiCrMo-3, and alloy 625. Electrodes should comply with AWS A5.11 ENiCrMo-12.

Hot Working

While cold forming is recommended wherever feasible, forging, upsetting and other operations can be performed at 1800- 2100 F . Temperatures above this range will cause scaling and a reduction in the workability of the material. Post-process annealing is required to re-attain maximum corrosion resistant properties.

Cold Working

Most common cold work methods are successful with this alloy. It should be understood however that the material will be more difficult to work than other austenitic stainless steels due its high work hardening rate. The resulting hardening will, however, produce increases in strength and toughness which may be of value in the finished product.


2100- 2200 F (1149- 1204 C ), followed by a water quench.