The density of ductile iron is similar to that of ordinary cast iron.
The weight difference between the two mainly depends on the volume and specific composition, rather than the density itself.
Density Comparison
The density of ductile iron is approximately 7.8 g/cm³, which is basically consistent with the density range of ordinary cast iron (such as gray cast iron and white cast iron) (6.6-7.8759 g/cm³).
Factors Affecting Weight
Volume: For the same volume, the weight difference between the two is negligible.
Composition: Ductile iron contains 3.2-3.8% carbon and 2.2-2.8% silicon, which may be slightly higher than the carbon and silicon content of ordinary cast iron (such as gray cast iron with 2.5-4% carbon and 1-3% silicon), but the difference is not enough to significantly change the density.
Practical Application
In industry, weight is usually calculated by volume. Since the densities of the two are similar, the actual weight difference depends on the specific part design.
Which has higher strength and toughness: ductile iron or cast iron?
Ductile iron has significantly higher strength and toughness than ordinary cast iron. A specific comparison is as follows:
Strength
Ductile iron: Tensile strength 400-1600 MPa, yield strength can be twice that of steel.
Ordinary cast iron: Tensile strength is only 80-340 MPa, and there is no clear yield strength.
Toughness
Ductile iron: Elongation 2%-20%, impact toughness ≥5J.
Ordinary cast iron: Elongation is close to 0%, highly brittle, and cannot withstand impact loads.
Reason
The graphite in ductile iron is spherical, which greatly reduces the cutting effect on the matrix, allowing the matrix strength utilization rate to reach 70%-90%; while the flake graphite in ordinary cast iron severely weakens the continuity of the matrix.
Of course, if you have a large-volume custom order for ductile iron or cast iron parts, you can choose to cooperate with Mulan Metal. Mulan Metal has 12 years of experience in the production and processing of cast parts and has helped customers in more than 30 countries complete the commissioned production of various cast parts, receiving consistent positive feedback. We look forward to your cooperation inquiry.
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