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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z	A Alloy The combination of two or more chemical elements, of which at least one is a metal. Usually possesses properties different from those of components (i.e., cast iron contains iron, carbon and silicon). Annealing A process involving heating and slow cooling applied in order to alter the mechanical or physical properties, particularly hardness-softening process. B Back Draft A reverse taper from the designed direction of draw from a pattern or core box. It prevents removal of a pattern from a mold without damage to the mold (Tear-ups). Bars Metal supports placed in a flask, usually the cope to reinforce the sand. Bath Molten metal pool in a ladle or furnace. BHN Brinell Hardness Number. Blasting A process for cleaning or finishing metal objects by the high velocity impingement of sand or hard metal shot against the surface of the objects. Blind Riser A riser not opened to the atmosphere (see Riser). Blower-core A machine using air pressure to fill a core box with sand. Boss A projection of circular cross-section on a casting, usually intended for drilling and tapping for attached parts. Brinell Hardness The value of hardness of a metal on an arbitrary scale representing kg/mm2. Burn-in or Burn-on A misnomer usually indicating metal penetration into molding and core sand, resulting in a mixture of metal and sand on a casting. C Cast Iron A term used to describe a series of ferrous alloys containing over 1.74% of carbon. Casting Metal object obtained by pouring molten metal into a mold. It also is the act of pouring metal. Chaplet Metal support used in molds to help hold cores in proper position. Chilled Edge or Surface (Crust) Rapid cooling of thin sections. It causes a very hard and brittle condition that is detrimental to machining. Choke A restriction in the feed system that controls the flow rate of metal into the mold cavity. Coke Fuel used in a cupola to melt charge materials. Source of some carbon found in iron. Cope Upper or topmost section of a mold, flask or pattern. Core Box Wood, metal or plastic box, the cavity of which has the shape of the desired core which is to be made therein. Core Print Projections on a pattern that form and locate cores in a mold. Also, projections on core or area in mold for the same purpose. Core Rod Steel rods imbedded in a core used to reinforce the core. Cup The portion of the gating system into which molten metal is introduced. Located on top of sprue or down gate. It is also called Pouring Basin or Runner Box. Cupola A vertical shaft furnace lined with refractories used to produce cast iron by high temperature melting of metallic and mineral charge materials. D Die Casting Forcing molten metal into permanent molds. It is also called Pressure Casting Draft The taper on vertical surfaces of a pattern, which allows easy withdrawal of pattern from compacted sand mixture. Drag Lower or bottom section of a mold, pattern or flask. Dross Metal oxides and other scum on the surface of molten metal. It is mostly a non-ferrous term. Ductile Iron Iron in which carbon is in the form of spherical nodules. It is also called Nodular Iron. E F Feed Metal The volume of molten metal from which a casting feeds as it shrinks (contracts) during solidification. Fin A thin projection of metal from the casting, formed as a result of imperfect mold or core joints. Flask A molding box into which molding sand is placed against the pattern while the box surrounds the pattern. It usually consists of a top and bottom (cope and drag). Flat-back A pattern with a flat surface at the joint of the mold. It lies wholly within the drag or cope, and this joint of the mold is a plane surface. Flow-off A large vent usually located at the high point of the mold cavity. In addition to letting air and mold gasses escape during a pour, the Flow-off fills with metal and is allowed to run or flow during the final stage of pouring. Fluidity The ability of molten metal to flow readily. Founding The sciences of melting and casting metals into useful objects that serve the needs of industry. It is better known as Metal Casting. G Gagger A metal piece of irregular shape (usually an L shape) used to reinforce and support sand in deep pockets of molds. There are two types: straight or hooked (cast or steel rods). Galling Galling is defined as a condition whereby excessive friction between high spots results in localized welding with subsequent splitting and a further roughening of rubbing surfaces of one or both of two mating parts. This is a type of adhesive wear where usually there is no loss of material. Factors controlling the gall resistance are nature of mating surfaces, lubrication, pressure between surfaces (P), relative speed (V), temperature, etc. The product function PV at which galling starts is a measure of gall resistance for metal couple for a given set of conditions. Gate The portion of the feed system where molten metal enters the mold cavity. It is also called an Ingate. Gating System The complete assembly of sprues, runners and gates in the mold. Green Sand Tempered (i.e., moistened molding sand). Green Strength The strength of molding sand containing moisture. Guide Pin The pin on a flask used to locate the cope in the proper place on the drag. Also to locate cheeks. H Head The pressure exerted by a fluid, as a head of molten metal. Heel Metal left in a ladle after pouring or in a furnace after or between tapping. Holding Furnace A vessel to hold and keep hot certain amounts of molten metal. I Inoculent Materials which when added to molten metal, modify the structure and thereby change the physical and mechanical properties. Investment Casting A process where patterns are removed by a melting or burning out process (i.e., lost wax process). J Jolt To raise the flask filled with sand and allow it to drop, thereby compacting the sand against the pattern. K Knock-off Riser Riser with a small attachment and can be knocked off with a hammer. L Ladle Metal barrel-like receptacles lined with a refractory material used to transport or pour molten metal. Lap-gate When the connection point of ingate to casting overlaps onto the cope surface (i.e., kiss-gate). Loose Pieces Part of a core box or pattern, which remains embedded in the core or mold and is removed after lifting off the core box or drawing the pattern. Back Draft is avoided by this means. M Mold The complete "box of sand" with the cavity inside and the gating system ready to accept the molten metal. Mold Wash Refractory emulsion coating used to coat cavity walls. It guards against penetration of metal into sand walls. Muller A type of sand mixing machine. Mulling The thorough mixing of sand, water and binding ingredients to form tempered, ready-to-use molding, or core sand. N O Oil Sand Core Core in which sand mass is bound by an oil-based binder. Open Riser Riser whose top is open to the atmosphere through the top of the mold. P Padding The process of adding extra material to a cross-section of a casting wall, usually extending from a riser to ensure adequate feed to a localized area where shrinking would occur if the added material were not present. Parting Line The joint where mold separates to permit removal of the pattern. Separates cope and drag. Pattern A form of wood, metal or plastic around which molding material is packed to produce a mold cavity for casting metals. Corresponds to shape desired for casting. Permanent Mold A long-life mold into which metal is poured by gravity. Pocket A body of sand surrounded on all but one side by molten metal. Pouring Basin The portion of the gating system into which molten metal is introduced. Located on top of sprue or down gate. It is also called Cup or Runner Box. Q R Ram Process of packing sand in a mold using a pneumatic or mechanized ramming device. Returns Metal in form of gates, sprues, risers or defective castings that are put back into the melting cycle. Riser A reservoir of molten metal to supply a contracting, cooling casting with make-up metal. It is used to prevent internal or external voids due to shrinkage. Riser, Blind A riser which is not open to the atmosphere. Runner The portion of the feed system that carries molten metal from the sprue to the gates (i.e., the metal distribution system). Runner Box The portion of the gating system into which molten metal is introduced. Located on top of sprue or down gate. It is also called Pouring Basin or Cup. Runner Extension The part of a runner that extends beyond the farthest ingate as a blind end. It acts as a dirt trap and is sometimes vented. S Scrap Metal to be remelted because of some imperfection. Shakeout The process of removing sufficiently cooled castings from a mold. Shell Mold Process Molds and cores having shell-like structures using thermosetting resins as binders, heated patterns and core boxes. Shot Metallic abrasive commonly used for cleaning casting surfaces. Shrinkage The difference in volume between liquid metal and solid metal in a given cavity. Slag The metallic impurities found floating atop a ferrous metal bath. Slag Trap An enlargement, dam or protrusion in the gating or runner system in a mold for the purpose of preventing molten slag particles from entering the mold cavity. Steel An alloy of iron and carbon, containing less than 1.74% carbon. Stool Device used on molding machine to hold pattern plate or refractory block used to support a crucible in a crucible furnace. Stress Raisers Factors such as sharp changes in contour or surface defects, which concentrate stresses locally. Strike-off Operation of removing excess sand from top of core box of flask. Metal bar used for same purpose. Stripping Removing the pattern from the mold or core from core box. T Tear-up A defect caused by back draft, damaged pattern or uneven drawing of a pattern. U Upset An addition to any flask part to increase height or depth. V Vent A small opening through which gases can escape during the pouring of a mold. W Washes Refractory coating applied to molds and cores to provide protection against penetration from molten metal. Wear Wear is damage to a solid surface, generally involving progressive loss of material due to relative motion between that surface and a contacting substance or substances (solid, liquid or gas). Types of wear include adhesive, abrasive, erosive, fretting, impact, etc. X Y Yield Comparison of finished casting weight versus total weight of metal poured in a mold. Z