Classification of Discontinuities

Inherent Discontinuities

1st stage of discontinuity

Related to the melting and initial solidification of metal in the ingot (i.e. original steel-making process) Inclusions, Porosity, Pipe.

Reasons for discontinuities and defects in metal?

The main reason for discontinuities and defects in metals are attributed to the processing of the ore to the casting process to the hot or cold working process.

Defect in casting: There are several casting defects which can be further classified in to five main categories:

1. Gas porosity.
2. Shrinkage defects.
3. Mould material defects.
4. Pouring metal defects.
5. Metallurgical defects.