Corten B steel

Corten B steel
ASTM Corten B steel grade is a hot rolled products of structural steels in technical delivery conditions with improved atmospheric corrosion resistance.The steel grade Corten B is according to ASTM standard which with the yield strength of 355MPa and 345MPa which is based on the different thickness.
Corten B – a weather resistant steel which is better suited for heavy and load bearing structures.
The material forms its own protective layer when exposed to atmospheric elements. Essentially, the top layer corrodes which then protects the steel beneath it. The natural finish does not normally require any form of maintenance such as painting, which makes the material a highly cost effective alternative to other structural steels.
Painting and maintenance will be required if the structure is is continually wet as a protective layer will not form. An good example is where the base of the structure meets with the ground or is partially submerged.

Grades & Equivalents

Corten	EN 10025-5:2004
Corten B	S355J2W

Chemical Components

Grade	C	Si	Mn	P	S	Cu	Ni	Cr	V	N
Corten-A	0.12	0.25-0.75	0.20-0.50	0.07-0.15	0.03	0.25-0.55	0.65	0.50-1.25
Corten-B	0.16	0.30-0.50	0.80-1.25	0.03	0.03	0.25-0.40	0.4	0.40-0.65	0.02-0.10

ASTM Corten B steel Mechanical properties:  
At room temperature for plates ≥3mm in thickness (transverse test specimans, according to EN 10002). Requirements to hot rolled plates ≤3mm in thickness according to EN 10025-5.

Grade	Thickness (mm)	Yield Strength MPa(min)	Tensile Strength MPa	Elongation % (min)
Corten B	≤16	355	470-630	20
	>16≤50	345

1 Mpa = 1N/mm2
The impact energy is determined on ISO-V longitudinal test specimens at a temperature of - 20°C as an average of three tests. For product thicknesses ≥10mm the average value is at least 27 J. For thicknesses between 10mm and 6mm, the minimum impact value is reduced proportionally to the specimen width (product thickness).

Corten B Steel Delivery state
Hot Rolled, Cold Rolled, Normalized, Quenched, Tempering, Thermal Mechanical Control Process (TMCP), Electroslag Remelting Technical, HIC test.