ASTM A588 Grade K (A588GrK) weathering steel plate is a high-strength, low-alloy structural steel featuring enhanced atmospheric corrosion resistance.
With a minimum yield strength of 345 MPa and a minimum tensile strength of 485 MPa, it is ideal for bridges, highway construction, and heavy structural applications exposed to outdoor conditions.
When properly exposed to the atmosphere, A588 Grade K forms a stable rust-like patina, significantly reducing the need for painting and maintenance.
Chemical Composition (% Max)
| Grade | C | Si | Mn | P | S | Ni | Cr | Mo | Cu | Cb |
|---|---|---|---|---|---|---|---|---|---|---|
| A588 Grade K | 0.17 | 0.25–0.50 | 0.50–1.20 | 0.04 | 0.05 | 0.40 | 0.40–0.70 | 0.10 | 0.30–0.50 | 0.005–0.05 |
Carbon Equivalent (Ceq) = [C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15] %
Mechanical Properties
| Grade | Yield Strength (MPa, min) | Tensile Strength (MPa, min) | Elongation in 8 in. (%) | Elongation in 2 in. (%) |
|---|---|---|---|---|
| A588 Grade K | 345 | 485 | 18 | 21 |
Density: 7.85 g/cm³
Hardness (Brinell): 150–170 HB
Typical Service Life: 40–60 years in outdoor environments without painting
Applications
Due to its superior corrosion resistance and strength, ASTM A588 Grade K steel plate is widely used in:
Bridge construction and long-span structures
Highway and railway frameworks
Industrial and urban infrastructure exposed to humidity or salt spray
Architectural projects - facades, sculptures, and decorative panels
In marine and urban industrial environments, corrosion rates are typically <0.02 mm per year, extending the lifespan of A588GrK by 3–5 times compared to ordinary carbon steel.
Additional Conditions & Testing
Heat Treatment Options: AR (As Rolled), N (Normalized), Q+T (Quenched & Tempered), TMCP (Thermo-Mechanical Controlled Process)
Testing:
UT (Ultrasonic Test) | Z-Direction (Z15, Z25, Z35) | Charpy V-Notch Impact Test | HIC Test | Third Party Inspection (SGS, BV)
Surface Treatment: Shot blasting, painting, anti-rust oiling, coating available on request
Supply & Logistics
Thickness: 6 – 200 mm
Width: 1500 – 4050 mm
Length: 3000 – 15000 mm
Monthly Supply Capacity: 5,000 MT
Delivery Time: 30–50 days (7 days for stock goods)
MOQ: 1 piece
Ports: Shanghai / Tianjin / Qingdao
Packing: Standard seaworthy export packaging or as required
