What is the material 254 SMO equivalent to?

What is 254SMO stainless steel?

254SMO (UNS S31254, ASTM F44, 1.4547) is a so-called super austenitic stainless steel. By increasing the molybdenum content to 6%, its pitting resistance equivalent (PREN) can reach over 43, similar to the performance of super duplex stainless steel (SDSS). 254SMO is non-magnetic, potentially easier to weld, and has a wider operating temperature range. However, due to its higher nickel and molybdenum content, it is significantly more expensive and has noticeably lower strength.

 

What is the material 254 SMO equivalent to?

The Unified Number System (UNS) designation for this high-grade steel is 31254. Still, there are many different names for stainless steel UNS 31254. Other common names include 254SMO or 6Mo. In Germany, the Werkstoff steel specification is 1.4547, also known as Alloy 254.

UNS Number	S31254
Wekstoff / EN Number	1.4529
EN name	X1CrNiMoCuN20-18-7
Other names	Alloy 254, SMO 254, 254SMO
ASTM Specifications	A479, A473, A240, F44

 

Other Designations

Other designations that are equivalent to stainless steel grade 254 SMO™ include the following.

ASTM A813	ASTM A469	ASTM A269	ASTM A240	ASTM A182 (F44)
ASTM A814	ASTM A312	ASTM A249

 

DIN 1.4547 Plate Chemical Formula

Grade	Ni	Cr	Mo	Cu	N	C	Mn	Si	P	S
SMO 254	17.5-18.5	19.5-20.5	6-6.5	0.5-1.0	0.18-0.22	0.02	1.0	0.08	0.03	0.01

 

Mechanical Properties

Elongation (%)	50
Tensile strength	98,600 (psi)
Yield Strength	43,5000 (psi)

 

Physical Properties (at Room Temperature)

Density	8.0 g/cm3
Electrical Resistivity	8.5 μohm/cm
Heat	500 J.kg-1.°K-1
Melting point	1320-1390°C
Thermal Conductivity	14 W.m -1.°K-1
Thermal Expansion	16.5 μm/μm/C

 

Heat treatment
The tubes are delivered in heat treated condition. If additional heat treatment is needed due to further processing the following is recommended.

Solution annealing
1150–1200°C (2100–2190°F), quenching in water. Thin-walled tubes min. 1130°C (2060°F), quenching in air/water.

 

What are the differences between SMO 254 and SS316?

Compared to stainless steel 316, SMO 254 has superior corrosion resistance, strength, and heat resistance, but it is more difficult to process and requires specific welding wire for welding.

 

What is the difference between hastelloy and smo 254?

The main difference lies in their properties: Hastelloy is a nickel-based alloy with high-temperature performance and excellent corrosion resistance; while 254 SMO is a special super austenitic stainless steel designed specifically for high chloride concentrations and acidic environments. Hastelloy is typically more expensive and used in extreme conditions.

 

What is the difference between 904L and 254 smo?

The main difference lies in the fact that 254 SMO is a high-strength super austenitic stainless steel with higher molybdenum and nitrogen content, thus exhibiting superior resistance to localized corrosion, such as pitting and crevice corrosion. In contrast, 904L is a more economical unstabilized austenitic stainless steel with good resistance to general corrosion, but lower overall strength and chloride resistance.

 

Applications
Stainless steel grade 254 SMO™ is used in the following areas:

Saltwater handling
Tall oil distillation columns
Flue gas desulfurization scrubbers
Components used in petroleum production
Food processing equipment
Process equipment in chemical industry
Bleaching equipment in the pulp and paper industry
Flue-gas cleaning
Desalination
Heat exchangers

If you have project requirements for 254 SMO stainless steel pipes, please feel free to place an order. GNEE has a large inventory of popular products for your selection. They can be processed into both seamless and welded forms. For detailed chemical composition and free samples, please contact our factory immediately. We offer competitive prices and excellent service.Email: info@gneestainless.com