Carbon steel plate, commonly known as mild steel, contains minimal alloy steel elements. Primary components include C, Mn, P, S, and Si, with no minimum limits for elements like Al, Cr, Ni, Mo, or V.
Low carbon steel is the most common form, offering excellent malleability and ductility. Medium carbon steel provides balanced ductility and strength with good wear resistance. High carbon steel delivers exceptional strength, while ultra-high carbon steel achieves greater hardness but loses malleability.
Mild steel (low carbon steel) contains minimal alloying elements, making it highly ductile, machinable, and weldable. While it cannot be hardened through heating and quenching, it offers excellent versatility for various applications.
Mild steel sheet plate is tough, strong, and stiff, ideal for welding, painting, machining, and drilling. Its magnetic properties and workability make it suitable for automotive repairs, engineering projects, and numerous DIY applications.
| Standard | Grade | C max | Mn max | Si max | P max | S max | Yield strength max | Tensile strength | Elongation% |
|---|---|---|---|---|---|---|---|---|---|
| JISG3101 | SS400 | 0.22 | 1.40 | 0.50 | 0.035 | 0.035 | 245 | 400-500 | 26 |
| ASTM | A36 | 0.25 | 0.80-1.20 | 0.40 | 0.045 | 0.050 | 250 | 400-520 | 26 |
| ASTM | A283 | 0.14-0.24 | 0.90 | 0.40 | 0.035 | 0.040 | 210 | 310-510 | 22-27 |
| GB700 | Q235A | 0.14-0.22 | 0.30-0.65 | 0.30 | 0.045 | 0.050 | 235 | 370-460 | 21-26 |
| GB700 | Q235B | 0.22 | 0.30-0.65 | 0.30 | 0.045 | 0.045 | 235 | 375-460 | 21-26 |
| GB700 | Q235C | 0.18 | 0.30-0.80 | 0.30 | 0.040 | 0.040 | 235 | 375-460 | 21-26 |
| GB700 | Q235D | 0.17 | 0.35-0.80 | 0.35 | 0.040 | 0.035 | 235 | 375-460 | 21-26 |
| EN10025 | S235JR | 0.17 | 0.65 | 0.35 | 0.030 | 0.030 | 225 | 360-510 | 18 |
ASTM A-36 is a structural quality carbon steel plate used in welded or bolted construction of bridges, buildings, and general structural applications. With a minimum yield strength of 36 ksi (250 MPa), A36 plate serves various purposes including railroad cars, trucks, agricultural equipment, trailers, construction equipment, buildings, and bridges.
High-strength low-alloy steel (HSLA) offers greater corrosion resistance than carbon steel. HSLA steels are specified by mechanical properties rather than chemical composition.