ASTM A588 Corrosion-Resistant Structural Steel Plate

Leeco® Steel stocks and supplies ASTM A588 corrosion-resistant structural steel plate. 


  • Corrosion-resistant, high-strength, low-alloy steel plate.
  • Available in three grades: A, B and K.
  • Often referred to as Corten or Weathering steel.
  • Ideal for welding, riveting or bolting in construction applications, primarily for bridges and buildings.
  • Suitable for many applications in bare or unpainted conditions when exposed properly.
  • Charpy test requirements may be requested.
  • May be certified to meet multiple specifications and/or standards on Mill Test Report, but guaranteed to be certified to meet ASTM A588 standards.


Available Sizes

Leeco Steel stocks the following standard sizes, but other sizes may be available for special orders.

A588 all grades 3/16" – 8" 48" – 120" Up to 480"

Minimum order weight in the USA is 20 tons. For orders weighing less than 20 tons, additional freight surcharges may be applied. Minimum order weight for orders outside of North America is 500 MT.

Material Properties

The following material properties are ASTM specifications and will be confirmed on the Mill Test Report.

Thickness Yield Point (ksi) Tensile Strength (ksi) Min. 2” Elongation %
4 in. and under 50 70 21
Over 4 in. to 5 in. 46 67 21
Over 5 in. to 8 in. 42 63 21


Chemical Composition

The following composition properties are ASTM specifications for these A588 grades.

Carbon 0.19% max
Manganese 0.80-1.25%
Phosphorus 0.030% max
Sulfur 0.030% max
Silicon 0.03-0.65%
Nickel 0.40% max
Chromium 0.40-0.65%
Copper 0.25-0.40%



Carbon 0.20% max
Manganese 0.75-1.35%
Phosphorus 0.030% max
Sulfur 0.030% max
Silicon 0.15-0.50%
Nickel 0.50% max
Chromium 0.40-0.70%
Copper 0.20-0.40%
Vanadium 0.01-0.10%


Carbon 0.17%
Manganese 0.50-1.20%
Phosphorus 0.030% max
Sulfur 0.030% max
Silicon 0.25-0.50%
Nickel 0.40% max
Chromium 0.40-0.70%
Molybdenum 0.10%
Copper 0.30-0.50%
Columbium 0.005-0.05%