What material is ASTM A588 Corten steel plate?
ASTM A588 steel plate is a high-strength low-alloy (HSLA) weathering structural steel grade specifically designed for long-term atmospheric corrosion resistance in outdoor environments. It is widely used in bridge construction, building facades, structural steel projects, vehicle structures, and landscape sculptures.
This steel is produced by adding copper (Cu), chromium (Cr), and nickel (Ni) to conventional low-alloy steel. The typical chemical composition ranges are approximately: copper (Cu) 0.20–0.40%, chromium (Cr) 0.40–0.65%, and nickel (Ni) 0.25–0.50% (values may vary slightly depending on specification and heat analysis). These alloying elements significantly enhance its resistance to atmospheric corrosion.


In natural exposure conditions, ASTM A588 steel typically begins to form an initial oxide layer within 3–6 months, and a stable, dense protective patina gradually develops within 1–3 years. This patina effectively blocks moisture and oxygen from penetrating further into the base metal, greatly slowing down ongoing corrosion.
Compared with ordinary carbon steel such as A36, ASTM A588 offers approximately 2–8 times better atmospheric corrosion resistance, depending on environmental conditions such as humidity, salinity, and industrial pollution. In most outdoor applications, it can significantly reduce or even eliminate the need for regular protective coating maintenance.
ASTM A588 steel plate typically has a minimum yield strength of about 345 MPa (50 ksi grade) and provides reliable structural durability. Over time, it develops a distinctive reddish-brown natural weathered appearance, achieving an excellent balance between functional performance and architectural aesthetics.
Specifications of ASTM A588 Corten steel plate
| Item | ASTM A588 Steel Plate |
|---|---|
| Standards | ASTM A588 / ASTM A588M |
| Specifications | High-Strength Low-Alloy Weathering Steel Plate |
| Grade | ASTM A588 Grade A / Grade B / Grade C |
| Width | 1000mm / 1250mm / 1500mm / 1800mm / 2000mm |
| Thickness | Hot rolled: 3mm – 100mm |
| Length | 2000mm – 12000mm or as per customer requirement |
| Surface | Hot rolled black surface / Natural weathering patina (after exposure) |
| Material | High-Strength Low-Alloy Weathering Steel (Cu-Cr-Ni alloyed steel) |
| Process | Hot Rolled / Controlled Rolling / Normalized (optional) |
|
Physical Properties A588 Weathering |
|||||
| Density | 0.28 lb/in3 | ||||
| Ultimate Tensile Strength | 70 ksi | ||||
| Yield Tensile Strength | 50 ksi | ||||
| Shear Modulus | 11,600 ksi | ||||
| Shear Strength | 51 ksi | ||||
| Hardness Rockwell | Brinell | B86 | 170 | ||||
| Elongation at Break Percentage | 22% | ||||
| Modulus of Elasticity | 29,700 ksi | ||||
| Poisson's Ratio | 0.28 | ||||
| Melting Point | 2,580-2,650 °F | ||||
| Electrical Conductivity | 7.4% IACS | ||||
|
Chemistry Information of A588 Weathering Steel Plate |
|
|
Element |
Percentage |
| Cr | 0.4 - 0.65 |
| Mn | 0.9 - 1.25 |
| C | 0.1 - 0.22 |
| Cu | 0.25 - 0.4 |
| Si | 0.15 - 0.3 |
| V | 0.02 - 0.1 |
| P | 0.04 max |
| S | 0.05 max |
| Fe | 97 - 98.5 |
Equivalent Standard For Corten Steel ASTM A588 Plate & Sheet
| APPLICATION | BRITISH STANDARD | JAPANESEJIS | GERMAN DIN |
AMERICAN ASTM |
| AIR PRE HEATERS | BS-6323-5 BS-6323-6 |
JIS G 3445 | DIN 17177 EN 10217-1 AND 2 EN 10305-2 AND 3 |
ASTM A423 GR.1 ASTM A214 |
Heat Treatment of A588 Corten Materiales
| Condition | Temperature (°C) |
|---|---|
| Stress Relieving | 550°C - 600°C |
| Normalising | 860°C - 940°C |
Aging of Rust for A588 Corten Plate

What are the differences between A588 Corten Plate and A36 carbon Steel Plate?
The main difference between ASTM A588 steel plate and ASTM A36 steel plate lies in the alloying element content and the resulting performance characteristics. ASTM A588 is a high-strength low-alloy weathering steel with added copper (0.20–0.40%), chromium (0.40–0.65%), and nickel (0.25–0.50%) compared to ordinary carbon steel.
Therefore, compared with A36, A588 typically offers approximately 2–8 times higher atmospheric corrosion resistance (depending on environmental conditions such as humidity, salinity, and industrial pollution). In natural exposure environments, it can form a dense and stable protective rust layer, significantly reducing or even eliminating the need for coating maintenance.
At the same time, A588 has a higher strength grade, with a minimum yield strength of about 345 MPa (50 ksi), while A36 has about 250 MPa (36 ksi).
As a result, ASTM A588 is more suitable for bridge engineering, outdoor steel structures, building facades, and long-term exposed structural applications, whereas ASTM A36 is a general carbon structural steel mainly used for general construction, mechanical parts, and non-corrosive structural applications.
A588 Weathering Steel Services
We can provide retreatment(Derusting,Lacquering,Painting,Sand Clusting),Heat treatment,UT Test,HIC Test,Impact Test,PWHT Z15 Test, Z25 Test, Z35Test,Cutting, Welding ,Inspection from the third party like SGS,Galvanization.

As a professional weathering steel exporter, if you require a quotation, please contact us to customize your required product specifications, including shape, condition, surface treatment, and processing technology.









