Grey cast iron contains graphite in the form of flakes. Named
after its grey fractured surface. C:3.0 – 4.0 wt%, Si: 1.0 – 3.0 %
Microstructure: graphite flakes in a ferrite or pearlite matrix
Weak & brittle in tension (the graphite flake tips act as stress
concentration sites).Stronger in compression,
Excellent damping capacity, wear resistance.
Microstructure modification by varying silicon content and
cooling rate
Casting shrinkage is low