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Machinability Of a Materials

Machinability is not an intrinsic property of a material, but rather the result of complex interactions between the workpiece and various cutting devices operated at different rates under different lubricating conditions. As a result, machinability is measured empirically, with results applicable only under similar conditions.



However, simply stated , it is the ease with which metal can be removed in various machining operations. Good machinability implies satisfactory results in machining.

The machinability of a metal is indicated by percentages what is termed machinability index. All machinability metals are compared to a basic standard. The standard metal used for the 100 percent machinability rating is free-cutting steel. Machinability index of carbon steels generally range from 40 to 60 percent, and that of cast iron from 50 to 80 percent. 

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