20# steel (20 carbon steel) is a high-quality low-carbon structural steel defined by Chinese standard GB/T 699. It is directly equivalent to AISI 1020 (USA) and EN C22 (Europe). With a carbon content of around 0.20%, 20# steel offers an excellent balance of strength, toughness, and plasticity. It is widely used for manufacturing mechanical parts, seamless steel pipes, boiler tubes, and components requiring good weldability and cold forming properties.
Chemical Composition
Typical chemical composition (% by mass) per GB/T 699 / ASTM A29.
| Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) |
|---|---|---|---|---|---|
| 20# / 1020 | 0.17–0.23 | 0.17–0.37 | 0.35–0.65 | ≤0.035 | ≤0.035 |
Note: 20# and AISI 1020 share nearly identical chemical compositions. 20# is defined by GB/T 699, while 1020 is defined by ASTM A29 / A108. Both offer excellent cold forming and welding performance.
Mechanical Properties
| Grade | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) | Hardness (HB) |
|---|---|---|---|---|
| 20# (Normalized) | ≥245 | ≥410 | ≥25 | ≤156 (Annealed) |
Available Sizes & Delivery
| Thickness (Plate/Sheet) | 0.5–200 mm |
| Diameter (Round Bar) | 10–500 mm |
| Outer Diameter (Pipe) | 6–630 mm |
| Forms Available | Plate, round bar, seamless pipe, tube, forging |
| Standard | GB/T 699 / GB/T 8162 / GB/T 8163 |
| Mill Test Certificate | EN 10204 3.1 with every shipment |
| MOQ | 3 Tons |
| Delivery Time | Within 7 days (≤500 tons) |
Why Order from Zhongtang Steel?
- Excellent Formability & Weldability — ideal for cold drawing and machining
- Consistent Quality — Strict control of C, Mn, and S for predictable performance
- EN 10204 3.1 MTC supplied with every shipment
- ISO 9001 certified manufacturer since 1998
- Mill-direct pricing — no trading company markup
Applications
- Seamless steel pipes for boilers, superheaters, and heat exchangers
- Mechanical parts such as shafts, gears, and fasteners
- Cold-rolled and cold-drawn steel products
- Automotive and agricultural machinery components
- Structural parts requiring good weldability
- Hydraulic and pneumatic tubing
Values are typical reference ranges per GB/T 699 / ASTM A29. Actual properties may vary by mill and production route. Mill test certificates (EN 10204 3.1) are supplied with every shipment — contact us for exact data sheets.
