Chemical Composition: Carbon (C ≤0.12%), manganese (Mn 0.30-0.60%), with sulfur (S ≤0.045%) and phosphorus (P ≤0.045%) to ensure basic toughness.
Mechanical Performance: Tensile strength 315-430MPa, elongation ≥30%. It has high plasticity, making it easy to bend, weld, and cold-form without cracking.
Typical Applications
General structural uses: Small brackets, bolts, nails, and lightweight frameworks in construction, furniture, or agricultural equipment.
Low-load components: Simple metal parts, wire rods, and cold-drawn products that don’t require high strength.

Chemical Composition: Carbon (C: 0.14-0.22%), manganese (Mn: 0.30-0.65%), silicon (Si: ≤0.30%), with sulfur (S ≤0.050%) and phosphorus (P ≤0.045%) as impurities.
Mechanical Performance: Tensile strength 375-500 MPa, elongation ≥26%. It has good ductility and plasticity, making it easy to weld, bend, and machine.
Typical Applications
Construction: Used in building frames, steel structures, brackets, and reinforcing bars for non-high-stress components.
General engineering: Fabrication of bolts, nuts, washers, simple machinery parts, and low-load structural components.
Manufacturing: Base materials for pipes, plates, or profiles in daily-use metal products.

Composition: Carbon 0.28-0.38%, manganese 0.50-0.80%, with strict impurity control.
Properties: Tensile strength 490-630MPa, elongation ≥20%, balancing strength and toughness.
Applications: Suitable for medium-load mechanical parts, structural brackets, bolts, etc.
Features: Higher strength, decent processability, cost-effective for mid-stress uses.

Chemical Composition: Carbon (C ≤0.10%), manganese (Mn ≤0.40%), silicon (Si ≤0.03%), with very low sulfur (S ≤0.035%) and phosphorus (P ≤0.035%). The ultra-low carbon and silicon content enhances its plasticity.
Mechanical Performance: Tensile strength 295-410 MPa, yield strength ≥175 MPa, elongation ≥35%. It has exceptional ductility, making it ideal for cold working (e.g., deep drawing, bending, stamping) without cracking.
Typical Applications
Cold-formed parts: Used in manufacturing thin-walled components, such as cans, buckets, automobile panels, and precision stamping parts.
Low-strength structural uses: Simple metal products like brackets, clips, and lightweight fittings where high plasticity is prioritized over strength.

Chemical Composition: Carbon (C: 0.07-0.14%), manganese (Mn: 0.35-0.65%), silicon (Si ≤0.17%), with strict impurity control (S ≤0.035%, P ≤0.035%).
Mechanical Performance: Tensile strength 335-410 MPa, yield strength ≥205 MPa, elongation ≥31%. It has good ductility, making it suitable for cold forming (bending, drawing) and welding.
Typical Applications
Cold-formed components: Pipes, tubes, and stamped parts (e.g., automotive fuel tanks, hardware fittings) requiring shaping without cracking.
Low-stress parts: Bolts, washers, and structural elements in machinery where high strength isn’t critical.
Seamless steel pipes: Often used as base material for low-pressure pipes in plumbing or general engineering.

Chemical Composition: Carbon (0.17-0.24%), manganese (0.35-0.65%), silicon (≤0.20%), with low impurities (S ≤0.035%, P ≤0.035%).
Mechanical Performance: Tensile strength 410-550 MPa, yield strength ≥245 MPa, elongation ≥25%. It balances ductility and strength, suitable for both cold working and mild heat treatment.
Typical Applications
Mechanical parts: Shafts, gears, bolts, and connectors in machinery (e.g., pumps, valves) where moderate strength is needed.
Piping: Used as base material for seamless steel pipes in low-pressure systems (water, gas, oil).
Fabrication: Cold-formed or welded components like brackets, sleeves, and structural fittings.

Chemical Composition: Carbon (0.27-0.34%), manganese (0.50-0.80%), silicon (0.17-0.37%), with controlled impurities (S ≤0.035%, P ≤0.035%).
Mechanical Performance: Tensile strength 540-660 MPa, yield strength ≥295 MPa, elongation ≥21%. It responds well to heat treatment (e.g., quenching and tempering) to further enhance strength.
Typical Applications
Mechanical components: Shafts, gears, connecting rods, and bolts in machinery requiring moderate load-bearing capacity.
Structural parts: Supports, brackets, and fittings in industrial equipment where strength is more critical than extreme ductility.
Fabricated parts: Welded or machined components that may undergo heat treatment for improved performance.

Chemical Composition: Carbon (0.52-0.60%), manganese (0.50-0.80%), silicon (0.17-0.37%), with strict impurity control (sulfur ≤0.035%, phosphorus ≤0.035%). The relatively high carbon content contributes to its strength and hardenability.
Typical Applications
Wear-resistant parts: Springs (e.g., leaf springs, coil springs), gear teeth, and clutch plates that require high surface hardness.
Load-bearing components: Shafts, pins, and connecting rods in machinery (e.g., agricultural equipment, construction machinery) subject to moderate to high stress.
Tools and fixtures: Simple cutting tools, punches, and dies where cost-effectiveness matters more than extreme toughness.

20Mn is a low-carbon manganese steel bar with ~0.20% C and 0.70-1.00% Mn, stronger than plain low-carbon steels.
Properties: Tensile strength 450-600MPa, yield strength ≥275MPa, elongation ≥24%. Good formability and weldability.
Applications: Machinery parts (shafts, gears), structural components, and cold-formed products needing higher strength than basic low-carbon steels.
Features: Balances strength and workability, cost-effective for medium-stress uses.