1.4547 material Equivalent

What is en 1.4547 material?

EN 1.4547 is a high-alloy super austenitic stainless steel, also known as UNS S31254 or 254 SMO, renowned for its exceptional corrosion resistance, particularly in chloride-rich and acidic environments like seawater, thanks to its high content of chromium, nickel, and molybdenum. It offers superior resistance to pitting, crevice corrosion, and stress corrosion cracking compared to common stainless steels, with good strength, weldability, and formability, making it ideal for marine, chemical processing, and desalination applications.

 

What is 1.4547 stainless steel equivalent to?

1.4547 stainless steel (also known as 254 SMO, UNS S31254, F44, 6Mo, or X1CrNiMoN20-18-7) is a super austenitic stainless steel with high levels of chromium, nickel, and molybdenum, giving it excellent resistance to pitting, crevice corrosion, and stress corrosion cracking, especially in chloride-rich environments like seawater, making it a high-performance alternative to common grades like 316L in demanding conditions.

Material No.	UNS	Alloy	AFNOR	EN	JIS	SIS	GOST
1.4547	S31254	254 SMO	Z1 CNDU 20.18.06Az	X1CrNiMoCuN20-18-7	–	2378	–

 

EN symbol (short)	X1CrNiMoCuN20-18-7
UNS	S 31254
AFNOR	X1CrNiMoCuN20-18-7 / NF EN 10217-7 (02/2005) (FR)
BS	X1CrNiMoCuN20-18-7 / B.S.EN 10217-7 (02/2005) (GB)
Registered work's label	254 SMO®

 

1.4547 Chemical Composition (% By Weight)

Title	UNS	Werkstoff	C	Si	Mn	P	S	Cr	Ni	Mo	Cu	N
6mo	S31254	1.4547	<0.02	0.7	1	0.03	0.01	20	18	6.1	0.75	0.2

 

1.4547 Physical Properties (Room Temperature)

Specific Heat (0-100°C)	500	J.kg-1.°K-1
Thermal Conductivity	14	W.m -1.°K-1
Thermal Expansion	16.5	μm/μm/°C
Modulus Elasticity	196	GPa
Electrical Resistivity	8.5	Ohm-cm
Density	8.0	g/cm3

 

1.4547 Mechanical Properties

Temper	Annealed
Tensile Rm	98	ksi (min)
Tensile Rm	675	MPa (min)
R.p. 0.2% Yield	45	ksi (min)
R.p. 0.2% Yield	310	MPa (min)
Elongation (2" or 4D gl)	35	% (min)

 

1.4547 Heat treatment:

Forging	1200 to 950 °C
Welding	weldable with all common welding processes
Annealing	Solution annealing at at least 1150 °C, followed by water quenching
Stress relieving annealing	at approx. 500°C
Hardening	no

 

Are 1.4547 and 254 SMO stainless steels similar?

1.4547 and 254 SMO stainless steel are the same material, just with different names: 1.4547 is the European (EN) standard number, while 254 SMO is the common trade name/generic name for this high-alloy super austenitic stainless steel (also known as UNS S31254 or 6Mo alloy).

 

1.4547 Stainless Steel  Corrosion Resistance
1.4547 stainless steel (commonly known as 254 SMO) offers exceptional corrosion resistance, especially in chloride-rich and seawater environments, with a very high PREN value of ~42–45 driven by its ~20% Cr, ~18% Ni, ~6% Mo, and nitrogen addition, delivering outstanding resistance to pitting, crevice corrosion, and stress corrosion cracking where standard 316L fails.

 

Is 1.4547 Stainless Steel Magnetic?
1.4547 is non-magnetic in the solution-annealed condition due to its fully austenitic microstructure; however, slight magnetism may develop after heavy cold working, which does not compromise its corrosion resistance.

 

What is the difference between 1.4404 and 1.4547?

1.4404 (316L) is a general-purpose low-carbon austenitic stainless steel, while 1.4547 (254 SMO) is a high-alloy super austenitic stainless steel containing higher levels of molybdenum (Mo) and nitrogen (N), suitable for extreme chloride/acidic environments and offering superior resistance to pitting and crevice corrosion. However, 1.4404 is less expensive and easier to weld/form. In short, 1.4404 is a general-purpose material, while 1.4547 is a specialized material.

 

 

If you have project requirements for 1.4547 stainless steel, we welcome your order. GNEE has a large inventory of popular products for you to choose from. It can be processed into various practical product forms, including plates, coils, tubes, bars, wires, etc. For detailed chemical composition information and free samples, please contact our factory immediately. We offer competitive prices and excellent service.Email: sales@gneestainless.com