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SOLUTIONS: Cast Iron

Ductile cast iron

General analysis of nodular irons:

Ductile cast iron (also known as nodular graphite iron, spheroidal graphite iron, and SG iron) bridges the gap between gray iron and steel.

Carbon

3,2–4,1%

Silicon Manganese Phosphorous Sulphur

1,8–2,8% Up to 0,8% 0,1% max.

0,03% max.

It meets the demands for increased size of equipment, higher operating speeds and lower production costs by having high strength, toughness, and a resistance to shock loading. By adding trace amounts of magnesium or cerium to the molten metal, the surface tension mechanism is altered and when the graphite precipitates it forms nodules or spheroids, instead of flakes as in gray iron, or compacted aggregates as in malleable iron.

This graphitic form dispersed thorough the casting contributes remarkable ductility to the casting, and creates strengths equaling many good grade steels, yet retains the advantages of superior castability and machinability. Ductile iron has mechanical properties approaching steel. It's tensile strength ranges from about 340 MPa to 1030 MPa as cast. It has yield strength from 275 MPa to 830 MPa with an elongation in 2 inches from 2% to 25%.

Ferrite

2.07

Graphite Nodules

In addition magnesium not in excess of 0,08%, or cerium in quantity of a few thosandths of 1% is included.

Ductile iron may be welded very satisfactorily with Unitor NIFE-334N

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