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What is Meehanite Cast Iron ? How It is made ?

MANUFACTURING OF MEEHANITE CAST IRON : 

Cast irons, in which metal has been treated with calcium silicide, are known by the trade name of meehanite. Calcium Silicide used to graphitize and fine graphite structure giving a cast Iron of  excellent mechanical properties. The high qualities of meehanite Iron are , however , not solely due to the use of calcium silicide but also due to careful control of all the factors in the melting of iron in the copula or electric furnace and in the molding of the casting. Very little calcium silicide remains in the iron after solidification.


The metal used is low in silicon, moderately low in carbon which is limited about 2.5 to 3 percent. This normally would be white if cast, but graphitizing by meehanite system of control provides a range of materials to meet the broad requirements by engineering industries.

There are in all more than twenty six types of  meehanite metal available at the present under five broad classification : 

(a) General Engineering,

(b) Heat Resisting,

(c) Wear Resisting,

(d) Corrosion Resisting,

(e) Modular "S" Type

All meehanite irons have high strength toughness, ductility and easy machinability. They therefore claim to bridge the gap between ordinary cast iron and steel. The castings weigh from 500 to 6000 kg. The metal is close - grained and shows a Brinell number of 200 to 210.

Meehanite iron responds to heat treatment unlike ordinary grey cast iron. It can be hardened either wholly or on the surface. It can also be toughened by the suitable treatment. Of the various applications, it is ideally suited for machine tool casting.   

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