A comparison of Casting and Forging

Casting Forging
There is no size limit to casing.  
Very large components are difficult to forge
Since the working is done in the molten stage,
metals can be added to form custom alloys during the process itself. 
Adding metals to the material is not possible
Very complex parts can be designed.
Difficult to make complex parts
Castings are hard and brittle.
Have excellent properties such as strength, toughness and ductility.
Risk of formation of cavities, porosity, etc.
No Risk of cavities, porosity, etc.
Lesser Wear Resistance
Greater Wear Resistance
Requires close supervision of the process by trained personnel.
The process is predictable and easy to monitor.
Grain direction cannot be controlled.
Grain direction can be controlled and oriented by design in order to achieve desirable qualities.
Longer lead times
Shorter lead times