5. Ancillary products

5.1 Coatings

Deposited on the surface of molds and cores, they are designed to modify the sand-metal interface, in order to avoid penetration defects or limit mold-metal reactions.

They take the form of a more or less fluid slip, consisting of a suspension of fine mineral materials in a liquid, a binder and various ingredients (thixotropic agents, fluidizers, wetting agents, etc.).

A distinction is made between covering and penetrating coatings. They can be applied by dipping, spraying or brushing, followed by thorough drying before pouring to remove the solvent.

Minerals include silica, chamotte, zircon, iron oxide, talc, graphite, magnesia, etc., used pure or in combination.

Suspension...