Glossary of Casting Terms (con't)
Impregnation – The Treatment of defective castings with a sealing medium to stop pressure leaks in porous areas, using soda, drying oils, plastics, and proprietary compounds.
Inclusions – Impurities trapped in the casting during solidification.
Insert – A part, usually formed from metal, which is placed in a mold and becomes an integral part of a casting.
Internal Shrinkage – A void or network of voids within a casting caused by inadequate feeding of that section during solidification.
Investment Casting – A pattern casting process in which a wax or thermoplastic is used. The pattern is invested by a refractory slurry. After drying, the pattern is melted or burned out of the cavity and molten metal is then poured into the resulting cavity.
Jacket Mold – A wooden or metal form, which is slipped over a mold made in a snap or slip flask, to support the four sides of the mold during pouring.
Jobbing Foundry – A casting facility equipped to economically produce a single casting or in small quantities from a pattern. The term is sometimes used to designate a commercial foundry.
Ladle – Metal receptacle frequently lined with refractories used for transporting and pouring molten metal.
Liquidus – A line on a binary phase diagram, or a surface on a ternary phase diagram, representing the temperatures at which freezing begins during cooling, or melting ends during heating.
Loose Piece – Core box; part of a core box which remains embedded in the core, and is removed after lifting off the core box. Pattern; laterally-projecting part of a pattern so attached that is remains in the mold until the body of the patter is drawn. Part of a permanent mold which remains on the casting, and is removed after casting is ejected from the mold.
Macrostructure – A line on a binary phase diagram, or a surface on a ternary phase diagram, representing the temperatures at which freezing begins during cooling, or melting ends during heating.
Mechanical Properties – Those properties of a material that reveal the elastic and inelastic reaction when force is applied. or that involve relationship between stress and strain. Also known as physical properties.
Metal Lot – A master heat that has been approved for casting and given a sequential number by the foundry.
Misrun – A casting not fully formed.
Mold – The form, made of sand, metal or refractory material, which contains the cavity into which molten metal is poured to produce a casting of desired shape
Mold Cavity – The impression in a mold produced by removal of the pattern. It is filled with molten metal to form the casting Gates and risers are not considered part of the mold cavity.
Mold Weight – A weight that is applied to the top of a mold to keep the mold from separating.
Molding Machine – A machine for making molds
Mulling – The mixing and kneading of molding sand with moisture and clay to develop suitable properties for molding.