Corten steel is a popular type of steel, used specifically in extreme weather conditions due to its high level of weather and corrosion resistance. While Corten steel is extremely popular, it can be considerably harder to source than standard Euronorm designated materials. This blog post will outline the properties of Corten steel and its alternatives, to provide an insight into other grades of steel that may be suitable for your application.

Corten Steel

As mentioned previously, Corten steel is a weather resistant steel that can also be called ‘Atmospheric Corrosion Resistant Steel’, and it is its alloying elements of copper and chromium that provide this level of atmospheric resistance.

Corten steel has a recognizable orange color, which is caused by the chemical composition forming a protective rust layer when exposed to extreme environments.

There are two main grades of Corten steel; Corten A and Corten B.

Corten A has added phosphorous, which makes it suitable for aesthetic facias and gas flue applications, while Corten B is better suited for heavy and load-bearing structures.

GradeThickness (mm)
Strip Products
Plate ProductsYield Strength
Rel N/mm²
Minimum
Tensile Strength
Rm N/mm²
Minimum
Elongation
A50 %
Minimum
Corten A2-126-1234548520

Corten A Chemical Composition

  
C0.15
Si0.25/0.75
Mn0.20/0.50
P0.07/0.15
S0.030
Al0.015/0.06
Cu0.25/0.55
Cr0.50/1.25
Ni0.65
GradeThickness (mm)
Strip Products
Plate ProductsYield Strength
Rel N/mm²
Minimum
Tensile Strength
Rm N/mm²
Minimum
Elongation
A50 %
Minimum
Corten B2-136-4034548519

Corten B Chemical Composition

 %
C0.19
Si0.30/0.65
Mn0.80/1.25
P0.035
S0.030
Al0.020/0.06
V0.02/0.10
Cu0.25/0.40
Cr0.40/0.65
Ni0.40

S355JOW

S355JOW is an equivalent weathering steel to Corten B. Like Corten steel, S355JOW builds its own protective layer to prevent the steel from oxidation.

GradeMin. Yield Strength ReH MPa     Tensile Strength Rm MPa  
Nominal Thickness (mm)Nominal Thickness (mm)
<16>16 <40>40 <63>63 <80>80 <100>100 <150>3>3 <100>100 <150
S355JOW355345335325315295510/680470/630450/600

S355JOW Chemical Composition

 %
C0.16
Si0.50
Mn0.50/1.50
P0.035
S0.035
N0.009
Cr0.40/0.80
Cu0.25/0.55

S355JOWP

This grade of weathering steel has added phosphorus, and it is the equivalent grade to Corten A. This metal also has excellent self-protective properties, due to the layer of rust that forms after reaction with the atmosphere. This grade finds use in long-lasting and economical structural steel solutions, such as bridges.

GradeMin. Yield Strength ReH MPa     Tensile Strength Rm MPa  
Nominal Thickness (mm)Nominal Thickness (mm)
<16>16 <40>40 <63>63 <80>80 <100>100 <150>3>3 <100>100 <150
S355JOWP355345510/680470/630

S355JOWP Chemical Composition

 %
C0.12
Si0.75
Mn1.00
P0.06/0.15
S0.035
N0.009
Cr0.30/1.25
Cu0.25/0.55

S355J2W

S355J2W is another grade that is equivalent to Corten B. It is an economical steel that is fully recyclable, and it can be used for either load-bearing applications or for cosmetic purposes in structures.

GradeMin. Yield Strength ReH MPa     Tensile Strength Rm MPa  
Nominal Thickness (mm)Nominal Thickness (mm)
<16>16 <40>40 <63>63 <80>80 <100>100 <150>3>3 <100>100 <150
S355J2W355345335325315295510/680470/630450/600

S355J2W Chemical Composition

 %
C0.16
Si0.50
Mn0.50/1.50
P0.030
S0.030
N0.009
Cr0.40/0.80
Cu0.25/0.55

Weathering Steel Products from Masteel

Masteel supply a range of weathering steel products to suit many applications, including Corten A, Corten B, S355JOW, S355JOWP, and S355J2W steels.

Our team can provide advice and support to anyone who needs a weathering steel and suggest the best solution for your application. If you would like any more information about our weathering steel solutions, including Corten steel, please contact us.