A588 is a weathering steel grade under the ASTM standard. Weathering steel refers to a type of low-alloy steel that gains excellent atmospheric corrosion resistance through the addition of small amounts of alloying elements. It is widely used internationally.
✅ 1. Chemical Composition
| A588 Grade A | A588 Grade B | ||
|---|---|---|---|
| <= 0.19 | <= 0.20 | ||
| 0.80–1.25 | 0.75–1.35 | ||
| <= 0.04 | <= 0.04 | ||
| <= 0.05 | <= 0.05 | ||
| >= 0.20 | >= 0.20 | ||
| 0.40–0.65 | 0.40–0.70 | ||
| <= 0.40 | <= 0.40 | ||
| 0.15–0.50 | 0.15–0.50 |
Note: Actual values may vary slightly depending on plate thickness and manufacturer.
to ordinary low-alloy steel, the corrosion resistance is significantly enhanced. The atmospheric corrosion resistance of weathering steel is 2 to 8 times that of ordinary carbon steel, and the longer it is exposed to the atmosphere, the more effective the protective patina becomes.
✅ 2. Mechanical Properties
| >= 50 ksi (345 MPa) - for <= 100 mm thickness | |
| >= 70 ksi (485 MPa) - for <= 100 mm thickness | |
| Elongation (in 200 mm) | >= 18% |
| Elongation (in 50 mm) | >= 21% |
✅ 3. Key Features
- Excellent atmospheric corrosion resistance (4–8x better than carbon steel)
✅ 4. Applications of A588 Steel Plate:
A588GrA, A588GrB, and A588GrC, especially where weight reduction or extended service life is desired-such as in .
This steel offers significantly better atmospheric corrosion resistance than carbon structural steels with or without copper, particularly when fully exposed to open air. It is suitable for use in
With its excellent weather resistance, structural strength, and long-term durability, ASTM A588 weathering steel is the ideal choice for outdoor applications exposed to harsh environments. Whether you're building bridges, industrial machinery, or architectural structures, selecting the right material is critical to performance and longevity.
A588 steel plates, available in multiple grades and thicknesses to meet the demands of your project. Backed by strict quality control and global export experience, we are committed to delivering reliable solutions that stand the test of time.
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