Is 1.4408 equivalent to SS316?

What is equivalent to 316 stainless steel?

The most common equivalents to 316 stainless steel are the European/Metric standard A4 or EN 1.4401, and the US/UNS standard UNS S31600. You may also see 316 referred to by its characteristics, such as Marine Grade stainless steel due to its increased corrosion resistance from added molybdenum, or the lower-carbon version, 316L (UNS S31603 or EN 1.4404).

 

What material is equivalent to 1.4408?
Yes, the European standard stainless steel EN 1.4408 (also known as GX5CrNiMo19-11-2) is equivalent to American standards like ASTM A351 CF8M and JIS 5121 SCS14A in Japanese standards, and is similar to AISI 316L stainless steel in its composition and properties. It is a cast austenitic stainless steel used for its corrosion resistance and is commonly found in industries such as oil and gas.

 

Is 1.4408 equivalent to SS316?

Yes, EN 1.4408 is a cast stainless steel that is the equivalent of the American casting grade CF8M, and is considered the cast version of SS316. While both share a similar chemical composition, their designations reflect their use: 1.4408 (or CF8M) is for cast products, whereas SS316 (or AISI 316) is for wrought products like plates, sheets, and bars.

 

Chemical Composition (wt. %)

Grade	C (max)	Cr	Ni	Mo	Mn	Si	P (max)	S (max)	N
1.4401 (AISI 316, wrought)	0.07	16.5–18.5	10.0–13.0	2.0–2.5	≤2.0	≤1.0	0.045	0.015	–
1.4408 (CF8M, casting)	0.07	18.0–21.0	9.0–12.0	2.0–3.0	≤1.5	≤1.5	0.04	0.04	–

 

Mechanical Properties (at room temperature)

Property	1.4401 (AISI 316)	1.4408 (CF8M)
Tensile Strength (Rm)	500–700 MPa	440–640 MPa
Yield Strength (Rp0.2)	≥200 MPa	≥200 MPa
Elongation (A5)	≥40%	≥30%
Hardness (HB)	≤215 HB	≤230 HB
Modulus of Elasticity	~193 GPa	~190 GPa

 

Weldability:

1.4401 has better weldability compared to 1.4408, making it more suitable for fabricated products requiring welding. 1.4408, with its slightly higher carbon content, may require post-weld heat treatment to prevent issues like sensitization.

 

Key Differences in Applications
Casting vs. Fabrication:
1.4408 is primarily used in casting applications. It is ideal for manufacturing parts like valves, pumps, and complex components that require high strength and corrosion resistance in cast form.
1.4401 is widely used in welded and fabricated applications, including pipes, tanks, pressure vessels, and other industrial equipment that require welding or complex forming processes.