Core 434/4113
EN 1.4113, ASTM 434 / UNS S43400

General characteristics

Outokumpu Core 434/4113 is a 1% molybdenum-alloyed ferritic stainless steel with medium chromium and normal carbon content, which can be used in many corrosive environments, such as at the cold end of automotive exhaust systems. After tensile elongation, Core 434/4113 may be prone to the ridging-surface phenomenon.

Typical applications

  • Automotive trim fittings


Product forms, available sizes and finishes


Product typeFinishesThicknessWidth
Black hot band1U2,50-8,501000-1350
Cold rolled coil2B, 2BB, 2C, 2E, 2F, 2G, 2J, 2K, 2R0,05-3,583-1530
Cold rolled sheet2B, 2BB, 2E, 2F, 2G, 2J, 2K, 2R0,30-3,5818-1530
Hot rolled coil, pickled1C, 1D, 1G, 1U2,00-8,0050-1550
Precision strip2R0,05-1,503-649
Chemical composition


The typical chemical composition for this grade is given in the table below, together with composition limits given for the product according to different standards. The required standard will be fully met as specified on the order.

The chemical composition is given as % by mass.

Typical 0.0516.51.0
ASME II A SA-240 ≤0.12≤1.0016.0-18.00.75-1.25
ASTM A240 ≤0.12≤1.0016.0-18.00.75-1.25
ASTM A240 ≤0.12≤1.0016.00-18.000.75-1.25
EN 10088-2 ≤0.08≤1.016.0-18.00.9-1.4
Mechanical properties



StandardRp0.2Rp1.0RmElongationImpact strengthRockwellHBHV
Product type: Cold rolled coil and sheet
Typical (thickness 1 mm)390420550
ASME II A SA-240 ≥ 240 ≥ 450
ASTM A240 ≥ 240 ≥ 450
ASTM A240 ≥ 240 ≥ 450 ≤ 89HRB
Product type: Hot rolled coil and sheet
ASME II A SA-240 ≥ 240 ≥ 450
ASTM A240 ≥ 240 ≥ 450
Product type: Hot rolled quarto plate
ASME II A SA-240 ≥ 240 ≥ 450
ASTM A240 ≥ 240 ≥ 450

1)Elongation according to EN standard:
A80 for thickness below 3 mm.
A for thickness = 3 mm.
Elongation according to ASTM standard A2” or A50.

Corrosion resistance

Outokumpu Core 434/4113 has good corrosion resistance in solutions of many halogen-free organic and inorganic compounds over a wide temperature and concentration range. It can withstand many sufficiently diluted organic and mineral acids depending on the temperature and concentration of the solution. Core 434/4113 may suffer from uniform corrosion in strong organic and mineral acids, as well as in hot concentrated alkaline solutions. If sensitized for intergranular corrosion due to welding or an inappropriate heat treatment, corrosion rates in certain environments may be significantly higher.

In aqueous solutions containing halogenides, e.g. chlorides or bromides, pitting and crevice corrosion may occur depending on the halogenide concentration, temperature, pH-value, concentration of oxidizing compounds, or crevice geometry, if applicable. The presence of corrosion inhibiting or accelerating compounds like e.g. transition metal ions or organic compounds may influence the corrosion behavior of Core 434/4113. Due to its ferritic crystal structure, Core 434/4113 is not prone to chloride-induced stress corrosion cracking.

Core 434/4113 can be used for indoor and outdoor applications in rural areas and urban environments where chloride contamination is low. The best material performance is typically achieved with the help of adequate design, correct post-weld treatment and regular cleaning during use (if applicable).

The maximum service temperature of Core 434/4113 in dry air is 800 °C. The presence of other corrosive compounds in the hot environment like water or sulfur compounds may reduce the maximum service temperature significantly.

For more information on corrosion resistance, please refer to the Outokumpu Corrosion Handbook or contact the our experts.

Pitting corrosion resistanceCrevice corrosion resistance

PRE Pitting Resistant Equivalent calculated using the formula: PRE = %Cr + 3.3 x %Mo + 16 x %N
CPT Corrosion Pitting Temperature as measured in the Avesta Cell (ASTM G 150), in a 1M NaCl solution (35,000 ppm or mg/l chloride ions).
CCT Critical Crevice Corrosion Temperature is the critical crevice corrosion temperature which is obtained by laboratory tests according to ASTM G 48 Method F


For a more detailed description of their corrosion resistance properties in different environments see Outokumpu Corrosion Handbook.

Physical properties



DensityModulus of elasticityThermal exp. at 100 °CThermal conductivityThermal capacityElectrical resistanceMagnetizable


More detailed information concerning welding procedures can be obtained from the Outokumpu Welding Handbook, available from our sales offices.

Standards & approvals



ASME SA-240M Code Sect. II. Part AUNS S43400 / 434
ASTM A240/A240MUNS S43400 / 434; UNS S43400 / 434
EN 10088-21.4113