Casting quality is influenced by a great many factors. Some of these factors concern only technical, respectively handling aspects.

In most cases metallurgical or chemical reactions must be considered. Examples are: Surface tension of the melt, "wetting" of the investment, shrinkage at solidification, segregations and dendritic structure. A main problem is the reaction of the melt with the investment. In this connection, influence of the atmosphere must be considered.

The influence of these above-mentioned factors may cause severe defects, as for example various kinds of porosity, inclusions, surface roughness.

Author: D. Ott