Forta 304L/4307
EN 1.4307, ASTM TYPE 304L / UNS S30403

General characteristics

Forta 304L/4307 is a low-carbon alternative to Core 304/4301. Forta 304L/4307 is an all- purpose product with good resistance to atmospheric and intergranular corrosion.

Typical applications

  • Beer kegs
  • Cutlery
  • Automotive components
  • Tanks and vessels
  • Furniture
  • Structural applications


Product forms, available sizes and finishes


Product typeFinishesThicknessWidth
Cold rolled coil and sheetWork hardened0,33-5,80≤ 1829
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.

TypicalForta 304L/43070.0218.18.1
ASTM A240/A240MTYPE 304L / UNS S30403<0.030<217.5-19.58.0-12.0<0.10Si:<0.75 P:<0.045 S:<0.030
EN 10088-21.4307<0.030<217.5-19.58.0-10.5<0.11Si:<1 P:<0.045 S:<0.030
Mechanical properties

StandardGradeRp0.2Rp1.0RmImpact strengthRockwellHBHV
Product type: Cold rolled coil and sheet
Typical (thickness 1 mm)Forta 304L/430729532565083HRB
Product type: Hot rolled coil and sheet
Typical (thickness 4 mm)Forta 304L/4307290345620175
Product type: Hot rolled quarto plate
Typical (thickness 15 mm)Forta 304L/4307260300580

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

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 information on corrosion resistance properties in different environments, use the online corrosion tables.

For more detailed information, please refer to the Outokumpu Corrosion Handbook.

Physical properties

Values according to EN 10088


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

*) Austenitic stainless steel grades may be magnetizable to a certain degree after cold deformation, e.g. in temper rolled condition.


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

Standards & approvals

This grade is often double certified as EN 1.4301/1.4307, ASTM Type 304/304L.

ASTM A240/A240MTYPE 304L / UNS S30403
EN 10088-21.4307


Download Outokumpu manufacturing site certificates and approvals.