Malleable cast iron has good plasticity and toughness, and hence the name "malleable", but it is actually not malleable. This is not stated in the mechanical foundation book. Does not forge mean the difficulty of metal undergoing plastic forming? Is plasticity and toughness malleable? Why do you say "actually not malleable"?

Because the flocculated graphite cuts and causes stress concentration on the cast iron metal matrix much smaller than that of gray cast iron, malleable cast iron has higher strength, especially plasticity (elongation δ up to ~12%) than gray cast iron It is much higher and has a certain plastic deformation ability, so it is named malleable cast iron (or malleable cast iron, also known as horse iron).

The graphite in malleable cast iron is in the form of floc, which has little cleavage and damage to the metal matrix, the stress concentration caused by the graphite tip is small, and the strength, plasticity and toughness of the metal matrix can play a large role.

Therefore, the mechanical properties of malleable cast iron are higher than gray cast iron, and the degree of plasticity and toughness are much higher.

The smaller the amount of flocculent graphite in malleable cast iron, the more regular the shape, the finer and more uniform the distribution, the higher the mechanical properties. No matter what the iron. High carbon content and brittle. The malleability of malleable cast iron only means that its plasticity is better than that of ordinary cast iron. It does not mean that it can be forged. In fact, its performance is not as good as that of ductile iron.

There is graphite in malleable cast iron. During forging, graphite will slip, forming flake defects, and its performance will be greatly reduced. So it cannot be forged. Because compared with other cast irons, he has relatively good plasticity and ductility, and his metallographic structure is floc, so it is called KT malleable to a certain extent.

Forging is only suitable for forging, but not forging. Because it still has graphite to cut the substrate.