1.4512 vs 1.4509 stainless steel: Differences

What material is 1.4512 equivalent to?

Material 1.4512 is a ferritic stainless steel, commonly known as AISI 409, UNS S40900, or X2CrTi12, a titanium-stabilized grade used for good corrosion/heat resistance, especially in automotive exhaust systems. It offers good ductility, stress corrosion cracking resistance, and a lower cost compared to other stainless steels, with JIS equivalent being SUS409 and AFNOR Z3CT12.

 

What is 1.4509 material grade?

Material grade 1.4509 is a ferritic stainless steel, also known as Type 441, that offers good corrosion resistance (similar to 304 stainless steel but often lower cost) and high-temperature performance, making it great for applications like automotive exhaust systems, catering equipment, and architectural panels due to its good weldability, formability, and polishing ability, stabilized with Titanium (Ti) and Niobium (Nb).

 

1.4512 vs 1.4509 Stainless Steel: Equivalent Materials Comparison

	1.4512 Stainless Steel (SUS409)	1.4509 Stainless Steel (SUS431)
	UNS S44409	UNS S43100
	SUS444, 1.4512, Stainless Steel 406	SUS430, 1.4509, Stainless Steel 431

 

1.4512 vs 1.4509 Stainless Steel: Chemical Composition

	1.4512 Stainless Steel (SUS409)	1.4509 Stainless Steel (SUS431)
	17.00% - 19.00%	16.00% - 18.00%
	1.00% - 2.00%
	<=0.030%	<=0.12%
	<=0.75%	<=0.75%
	0.50% - 1.50%	0.50% - 1.50%
	<=1.00%	<=1.00%
	<=0.045%	<=0.04%
	<=0.015%	<=0.03%

 

1.4512 vs 1.4509 Stainless Steel: Mechanical Properties

	1.4512 Stainless Steel (SUS409)	1.4509 Stainless Steel (SUS431)
	485 - 620 MPa (70 - 90 ksi)	480 - 600 MPa (69 - 87 ksi)
	275 MPa (40 ksi)	205 - 290 MPa (30 - 42 ksi)
	>=20%	>=25%
	170 - 220 HB	150 - 190 HB
	200 GPa (29 x 10⁶ ksi)	200 GPa (29 x 10⁶ ksi)
	7.80 g/cm³	7.75 g/cm³
	14.9 W/m·K	15.0 W/m·K
Thermal Expansion (20-100℃)	11.0 μm/m·℃	11.4 μm/m·℃

 

What is the density of 1.4512 stainless steel?
The density of EN 1.4512 stainless steel is 7.7 g/cm³. This value is due to its ferritic base and low alloy composition, which is slightly lower than the density of nickel-containing austenitic steels (e.g., 304, with a density of 8.0 g/cm³). This makes it a suitable reference for lightweight component selection.

 

1.4512 vs 1.4509 Stainless Steel: Magnetism
EN 1.4512 is purely ferritic in structure, with a body-centered cubic (BCC) arrangement, making it magnetic in all states. 1.4509, however, has a ferritic-austenitic "lean duplex" structure, where the austenitic phase is non-magnetic, making the overall material weakly magnetic or nearly non-magnetic (its magnetism is much lower than 1.4512).

 

1.4512 vs 1.4509 Stainless Steel: High-Temperature Resistance
EN 1.4512 stainless steel can withstand continuous temperatures of about 600–750℃, with short-term peaks around 800℃. The stability of the oxide layer depends on the combination of chromium and titanium. On the other hand, 1.4509 stainless steel contains a small amount of austenitic phase and molybdenum, allowing it to maintain better oxidation resistance at about 800–900℃ for short periods. Its long-term service temperature limit is around 750–800℃. Therefore, 1.4509 exhibits superior high-temperature stability to 1.4512 in harsher environments with higher temperatures or thermal cycling.

1.4512 vs 1.4509 Stainless Steel: Applications
EN 1.4512 stainless steel is primarily used in automotive exhaust systems (muffler casings, catalytic converter housings, resonators) and industrial silencers, making up approximately 80% of its market. 1.4509 stainless steel is suitable for applications such as heat exchangers, chemical vessels, marine light-load components, and high-temperature corrosion-resistant structures.

 

 

At GNEE, 409 ss is available in various forms to meet diverse industrial needs:





Testing and Documentation: Mill Test Certificates, EN 10204 3.1, Chemical Reports, Mechanical Reports, Destructive Testing Reports, Non-Destructive Testing Reports, PMI Test Reports, Visual Inspection Reports, Third-Party Inspection Reports, NABL Certified Laboratory Reports.
Packaging: Wooden crates, bubble wrap, steel strapping, or packaged according to customer requirements.