In Centrifugal Casting process, the moulds / dies are rotated at very high speeds (more than 1000rpm) creating a centrifugal force. The liquid metal is thrown to the outside diameter, where it gets cooled against the mould/die wall i.e. the solidification takes place from the outside to inside. The less dense material such as impurities 'float' to the bore and are subsequently removed during proof machining.
The centrifugal process creates a very tight and defined grain structure due to the directional solidification of molten metal under high pressure. The castings produced by this process are free from surface / sub-surface defects & have almost nil porosity.
| CENTRIFUGAL CASTINGS | SAND / STATIC CASTINGS |
| Dense & Even micro structure (No Porosity) | Spongy and uneven micro |
| Radial & uniform grain flow | Linear & non-uniform grain |
| Better tensile strength. | Low tensile strength. |
| Hardness is more & hardness uniform. | Low and non-uniform |
| Withstands impact loads. | Doesn't withstand impact loads. |
| Excellent surface finish. | Poor surface finish. |
| Free from micro porosity. | Micro-porosity is present. |
| Life is better. | Life is comparatively less. |
