The Short Answer
Use Mild Steel (MS) for structural fabrication, tanks, frames, and general welded construction. Use EN8 when you need a machined component with moderate-to-good strength — shafts, studs, gears, and turned parts.
Chemical Composition
| Element | Mild Steel (IS 2062) | EN8 (C45) |
|---|---|---|
| Carbon (C) | 0.15–0.25% | 0.36–0.44% |
| Manganese (Mn) | 0.40–1.50% | 0.60–1.00% |
| Silicon (Si) | 0.40% max | 0.10–0.40% |
| Sulphur (S) | 0.045% max | 0.050% max |
The key difference is carbon content. EN8's higher carbon (up to 0.44% vs 0.25% max for MS) is what gives it superior strength and hardness potential.
Mechanical Properties
| Property | Mild Steel (IS 2062) | EN8 (Normalised) |
|---|---|---|
| Tensile Strength | 410–560 MPa | 700–850 MPa |
| Yield Strength | ≥ 250 MPa | ≥ 465 MPa |
| Elongation | ≥ 23% | ≥ 16% |
| Hardness | 120–140 HB | 201–255 HB (H&T) |
| Machinability | Good | Good–Very Good |
| Weldability | Excellent | Fair (pre-heat required for thicker sections) |
When to Use Mild Steel
Structural welding: MS is easy to weld without pre-heat and joins reliably — ideal for frames, plates, tanks, gussets.
Budget fabrication: MS is the cheapest steel option per tonne — use it where higher alloy costs aren't justified.
CNC profile-cut blanks: MS plates are our most commonly CNC-cut material — available in all thicknesses at our Ghaziabad yard.
When to Use EN8
Shafts & spindles: EN8 offers the strength for moderate-load shafting — it's the first step up from MS for rotating machinery.
Turned components: EN8's machinability (especially EN8D free-cutting variant) makes it ideal for CNC turning on automatic lathes.
When through-hardening is needed: EN8 can be hardened and tempered to improve surface hardness for wear applications.