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Manufacturing of Alloy Cast iron

Alloy Cast Iron have been developed in recent years to overcome certain inherent deficiencies in ordinary cast Iron and to give qualities more suitable for special purposes. The addition of nickel, chromium, molybdenum, titanium, silicon, copper and other alloying elements confer special properties to this cast Iron.

The use of 1 or 2 percent of nickel is suitable good quality iron offers a simple and effective means of improving the properties to this cast iron. It ensures machinability and uniformity of structure of the cast iron. By the use of nickel of the order of 25 percent, enhanced life can also be obtained in parts subjected to abrasive wear. Cylinders or cylinder liners of all sizes form the smallest to the largest afford outstanding examples. Nickel Cast Iron is also used in withstanding caustic corrosion. For this reason. It is widely employed for making caustic pots, pipes and other castings in contact with  caustic liquor. The addition of only 1 percent of nickel gives as all round benefit for this purpose. The most useful reason for using nickel in cast Iron is to obtain density and pressure tightness in castings with large and varying sections. This has led to the application of nickel cast for many parts of steam and hydraulic machinery , compressors and internal combustion engines.



Where Improvement in the wearing quality is of importance, chromium additions with the nickel are often found useful. Cast iron alloyed in this manner finds wide application for pumps of all types in which frictional, as well as erosive, wear has to be considered. Alloy cast iron containing 10 to 30 percent chromium and 1 to 3 percent total carbon, also exhibits a high degree of heat resistance combined with strength at high temperatures. 

Cast iron alloyed with 10 % Nickel and 6 percent manganese become non-magnetic. A special non-magnetic patented cast Iron is known under the name of  "Nomag".   

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