Ductile iron

Ductile ironWith properties similar to certain types of steel, ductile iron is a good, inexpensive alternative that can be used in casting parts. Ductile cast iron is obtained by adding magnesium to molten cast iron. This delays the solidification process and causes spherical graphite nodules to appear.

Ductile iron, or spheroidal cast iron, is an alloy made from iron, carbon and silicon. It contains graphite in the form of nodules, which eliminates the risk of crack propagation. This property make it more resistant than gray iron, in addition to increase its yield strenght and maximum strenght. Although its properties are similar to those of steel, its cost is much lower. In addition to sharing many properties with gray iron (ease of molding, ease of machining, resistance to compression, abrasion and wear), ductile iron displays the following characteristics:


Advantages of Ductile iron

  • Fracture resistance
  • Impact resistance
  • High elastic limit
  • Substantial elongation
  • Ductulity
Ductile iron properties
ASTM A-536 Grade Yield strenght (PSI) Elastic limit  Elongation %  Typical Brinell hardness
60-40-18 60 000 40 000  18  174-217
65-45-12 65 000 45 000 12 179-228
80-55-06 80 000 55 000 6 207-241
100-70-03 100 000 70 000 3 228-269


Equivalent grades of ductile iron
ASTM A-536 Grade DIN 1693 EN 1593 ISO 1083
60-40-18 GGG-40 EN-GJS-400-18  400-18
65-45-12 EN-GJS-400-10 450-10
80-55-06 GGG-50 EN-GJS-400-3 600-3
100-70-03 GGG-60 EN-GJS-400-2 700-2