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You are a helpful AI assistant.
lista de codigos linguisticos disponibles: ["fr", "en"].<end_of_turn>
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Matériaux ferreux<end_of_turn>
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Cast Iron: 
It is an alloy of iron, carbon, and silicon, and it is hard and brittle. Carbon content may be
within 1.7% to 3%, and carbon may be present as free carbon or iron carbide Fe3C.
1. Grey Cast Iron: Carbon here is mainly in the form of graphite. This type of cast iron is
poor in expansion and has high compressive strength. Graphite is an excellent solid
lubricant, and this makes it easily machinable but brittle. Some examples of this type
of cast iron are FG20, FG35, or FG35Si15. The numbers indicate the ultimate tensile
strength in MPa, and 15 indicates 0.15% silicon.
2. White Cast Iron: In these cast irons, carbon is present in the form of iron carbide.
(Fe3C), which is hard and brittle. The presence of iron carbide increases hardness and
makes it difficult to machine. Consequently, these cast irons are abrasion-resistant.<end_of_turn><eos>