Material Knowledge
Understanding gray iron and ductile iron — the foundation of high-performance cast components.
Get Expert Advice →Gray Iron vs. Ductile Iron
The key difference lies in the shape of graphite particles: gray iron contains flakes while ductile iron contains nodules (spheroids). This microstructure difference dramatically affects mechanical properties.
Gray Iron (Flake Graphite)
Excellent vibration damping, high thermal conductivity, and superior machinability. Ideal for machine bases, engine blocks, and brake drums.
Ductile Iron (Nodular Graphite)
High tensile strength, impact resistance, and ductility – comparable to cast steel. Perfect for gears, suspension components, and pipe fittings.
Mechanical Properties Comparison
| Property | Gray Iron (HT250) | Ductile Iron (QT500-7) |
|---|---|---|
| Tensile Strength (MPa) | 250 | 500 |
| Yield Strength (MPa) | – (no yield) | 350 |
| Elongation (%) | <1 | 7 |
| Hardness (HB) | 180–250 | 170–230 |
| Impact Resistance | Low | High |
| Damping Capacity | Excellent | Good |
Other grades available: HT200, HT300, QT400-15, QT600-3, QT700-2, etc. Contact us for full datasheets.
Where to Use Each Material
Gray Iron is the first choice for components requiring vibration control, thermal cycling stability, and cost-effective complex shapes: machine beds, engine blocks, brake drums, pump housings.
Ductile Iron replaces steel in many applications due to its strength, toughness, and castability: automotive suspension arms, heavy-duty gears, pipeline valves, wind turbine hubs.
Matson Iron Casting helps you select the optimal material based on mechanical requirements, operating environment, and budget.
Discuss Your Application →Download Free Material Selection Guide
Get detailed technical datasheets, property charts, and application recommendations for gray iron and ductile iron.
Download PDF Guide →Ready to Source High-Quality Castings?
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