The Glossary of Foundry and Casting
(C-D-E)

To help metal casting buyers and sellers to understand more about metal casting and foundry operation terms. All terms have been arranged in alphabetical order.

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

C or Croning Process
See Shell Molding.

Computer Aided Design (CAD)
The computer software/hardware used to produce part drawings electronically.

CAE
Abbreviation for Computer Aided Engineering.

Calcium Boride
An alloy of calcium and boron corresponding (when pure) to the formula CaB6, containing about 61% boron and 39% calcium, and used in deoxidation and degasification of nonferrous metals and alloys.

Calcium Carbide
A grayish-black, hard crystalline substance made in the electric furnace by fusing lime and coke. Addition of water to calcium carbide forms acetylene and a residue of slaked lime. See Electric Furnace.

Calcium Molybdate
A crushed product containing 40-50% molybdenum, 23-25% lime, 3% iron maximum and 5-10% silica, used to add molybdenum to iron and steel produced in the open hearth, air furnace, or electric furnace. See Open Hearth, Air Furnace, Electric Furnace.

Calcium Silicon
An alloy of calcium, silicon, and iron containing 28-35% Ca, 60-65% Si, and 6% Fe, maximum used as a deoxidizer and degasser for steel and cast-iron; sometimes called calcium silicide.

Calcium Wired Injection
Wire feeding of steel clad calcium wire into molten bath to provide favorable kinetics for inclusion modification.

Calcium-Aluminum-Silicon
An alloy composed of 10-14% calcium, 8-12% aluminum, and 50-53% silicon, sued for degasifying and deoxidizng steel. See Alloy.

Calcium-Manganese-Silicon
An alloy containing 17-19% calcium, 8-10% manganese, 55-60% silicon, and x0 to 14% iron, used as a cavenger for oxides, gases, and nonmetallic impurities in steel. See Alloy.

Camber
Deviation from edge straightness usually referring to the greatest deviation of side edge from a straight line.

Captive Foundry
A foundry that is an operating part of a manufacturing plant, and whose production products, castings, are used within the plant as parts of finished objects.

Carbide
A compound of carbon with a more positive element, such as iron. Carbon unites with iron to form iron carbide or cementite, Fe3C. See Cementite.

Carbon
Element occurring as diamond and as graphite. Carbon reduces many metals from their oxides when heated with the latter, and small amounts of it greatly affect the properties of iron. Though classed as a nonmetallic, metallurgically, like boron, it is treated as a metal.

Carbon Boil
Refers to the practice of adding oxidizing agents such as iron ore or oxygen to molten steel in the furnace to react with carbon and create a boiling action. In addition to reducing the carbon content, it removes occluded gasses such as hydrogen, oxygen, and nitrogen. See Boil.

Carbon Dioxide Process (Silicate process, Schmidt Philip process)
A process for hardening molds or cores in which carbon dioxide gas is blown through dry clay-free silica sand to precipitate silica in the form of a gel from the sodium silicate binder. See Silica Sand.

Carbon Equivalent
Relationship of total carbon, silicon, and phosphorus in gray iron, expressed by the formula CE=TC%+Si%/3+P%/3.

Carbon Sand
A molding aggregate consisting principally of carbon (graphite) granules.

Carbon Steel
Steel which owes its properties chiefly to various percentages of carbon without substantial amounts of other alloying elements; also known as ordinary steel or straight carbon or plain carbon steel.

Carbon, Combined
The carbon in iron or steel which is combined with other elements and therefore is not in the free state as graphite or as temper carbon. See Temper Carbon.

Carbonitriding (Nicarbing)
A process in which a ferrous alloy is case hardened by first being heated in a gaseous atmosphere of such composition that the alloy absorbs carbon and nitrogen simultaneously, and then being cooled at a rate that will produce desired properties.

Carburizing
A form of case hardening that produces a carbon gradient inward from the surface, enabling the surface layer to be hardened by either quenching directly from the carbonizing temperature or by cooling to room temperature, then reaustenitizing and quenching.

Case
The surface layer of an iron-base alloy which has been suitably altered in composition and can be made substantially harder than the interior or core by heat treatment.

Case Hardening
A process of hardening a ferrous alloy so that the surface layer or case is made substantially harder than the interior or core. Typically case hardening process are carburizing, carbonitriding, and nitriding. See Carburizing, Carbonitriding, and Nitriding.

Cast Iron
Iron shaped using any number of casting processes. Gray Iron is by far the oldest and most common form of cast iron. As a result, it is assumed by many to be the only form of cast iron and the terms "cast iron" and "gray iron" are used interchangeably. Generic term for a series of alloys of iron, carbon, and silicon, in which the carbon is in excess of the amount which can be retained in solid solution in austenite at the eutectic. When cast iron contains a specially added element or elements in amounts sufficient to produce a measurable modification of the physical properties under consideration, it is called alloy cast iron. Silicon, manganese, sulfur, and phosphorus, as normally obtained from raw materials, are not considered as alloy additions. Term used to describe a series of ferrous alloys containing over 1.74% of carbon. See Alloy, Gray Iron, Iron.

Cast Plate
Metal plate, usually aluminum, cast with the cope pattern on one side and the drag pattern on the other. See Matchplate.

Casting (verb)
A process where molten metal is poured into a mold and solidification is allowed to take place. The act of pouring metal.

Casting (noun)
A metal object obtained by pouring molten metal into a mold. The metal shape, exclusive of gates and risers, that is obtained as a result of pouring metal into a mold. See Gate, Riser.

Casting Defect
A defect in a casted object or casting.

Casting Drawing
An engineering drawing which depicts the shape and size of a part to be cast.

Casting Industry
Is the sixth largest Industry in North America, behind Petroleum, Agriculture, Lumber, Mining, Textile, Transportation according to data supplied by the AFS. The Casting Industry is the making of products from metals, earth, glass, etc. See AFS.

Casting Layout
A check of dimensions against applicable drawings and specifications.

Casting Porosity
The porosity of a casting artifact.

Casting Process
A forming process in which a molten metal, polymer, or other heated liquid or plastic material is poured into a mold or onto a substrate with little or no pressure applied; the substance cools, solidifies, and the formed object is removed.

Casting Strains
Strains resulting from internal stresses created during cooling of a casting.

Casting, Machine (verb)
Process of casting by machine.

Casting, Open Sand (noun)
Casting poured into an uncovered mold.

Cast-Weld
Welding one casting to another to form a complete unit. See Fabrication.

Cast-Weld Assembly
Welding one casting to another to form a complete assembly.

Cavitation
The formation and collapse of cavities or bubbles within a liquid.

Cavity, Mold Or Die
Impression or impressions in a mold or die that give the casting its shape. See Casting (noun).

Cement
Mineral substances in finely divided form, which are hardened through chemical reaction or crystallization. A common one is Portland cement.

Cement Molding
Process in which the sand bonding agent is a type of portland cement that develops high strength early in the hardening stage. Approximately 13 pounds of cement, 6 pounds of water, and 100 pounds of clayfree sand are mixed together. This mixture must be used within 3 to 4 hours. Molds are air dried for 72 hours before use.

Cement, Refractory
Highly refractory material in paste or dry form, ready to be mixed with water which may be used as a mortar, a patching material, or to form a complete lining in a furnace or other unit where high temperatures are encountered.

Cementation
Process of introducing elements into the outer layer of metal objects by means of high-temperature diffusion.

Cementite
A hard brittle, crystalline compound of iron and carbon commonly known as iron carbide and having the approximate chemical structure, Fe3C. Cementite is characterized by an orthorhombic crystal structure.

Centrifugal Casting (verb)
Process of filling molds by pouring the metal into a sand or metal mold revolving about either its horizontal or vertical axis, or pouring the metal into a mold that subsequently is revolved before solidification of the metal is complete. Molten metal is moved from the center of the mold to the periphery by centrifugal action.

Centrifugal Casting (noun)
Casting made in molds which are rotating so as to produce a centrifugal force in the molten metal. See Casting.

Ceramic Mold
Mold in which the refractory and binder are such that when fired at high temperature, a rigid structure is formed. Mold can be made in a flask or in the form of a shell. See Binder, Flask, Mold.

CERCLA
Abbreviation for Comprehensive Environmental Response, Compensation and Liability Act. 1980.

Cereal
Substance derived principally from corn flour, which is added to the core and molding sands to improve their properties for casting production. See Core, Molding Sands.

Cerium
Metallic element, malleable and ductile, most abundant of rare-earth group. Atomic weigh 140.13, sp. Gr. 7.04, hardness (Mohs) about 2, melting point 640°C. Has exceptionally strong affinity for oxygen, sulfur, hydrogen, nitrogen, etc.

Ceroxide
See Inclusions.

Chalk Test
Method of crack detection which consists of applying a penetrating liquid to the part, removing the excess from the surface which is then coated with whiting or chalk. After a short time the penetrant seeps out of the cracks into the whiting, causing an appreciable difference in whiteness.

Chamfer
Breaking or beveling the sharp edge or angle formed by two faces of a piece of wood or other material.

Chamotte
Coarsely graded refractory material prepared from calcined clay and ground firebrick mulled with raw clay, used in steel foundries.

Chaplet
Metal supports or spacers used in molds to maintain the cores, or parts of a mold, which are not self-supporting. Chaplets maintain these dimensions during the casting process, they then become part of the casting itself as the molten metal solidifies around the chaplet and fuses it into the finished casting.

Charcoal (Pig) Iron
Pig iron reduced in a blast furnace, using charcoal as the fuel. See Blast Furnace.

Charging Crane
System for charging the melting furnace with a crane.

Charging Door
Opening through which the furnace is charged.

Charging Floor
Floor from which the furnace is charged.

Charging Machine
Machine for charging the furnace, particularly the open hearth.

Charpy Impact Test
A pendulum type of impact test which a specimen, supported at both ends as a simple beam, is broken by the impact of the falling pendulum. Energy absorbed in breaking the specimen, as determined by the decreased rise of the pendulum, is a measure of the impact strength of the metal. See Brinell Hardness Test.

Cheek
Intermediate sections of a flask inserted between cope and drag. Necessitated by difficulty in molding unusual shapes, or in cases where more than one parting line is required.

Chicken Wire Cracks
See Craze Crack.

Chill (External)
Metal, graphite or carbon blocks that are incorporated into the mold or core to locally increase the rate of heat removal during solidification and reduce shrinkage defects. See Directional Solidification, Solidification.

Chill (Internal)
A metallic device / insert in molds or cores at the surface of a casting or within the mold to increase the rate of heat removal, include directional solidification and reduce shrinkage defects. The internal chill may then become a part of the casting. See Casting, Core, Mold.

Chill (noun)
A device used to cool an isolated area of a mold.

Chill Coating
A material applied to metal chills to prevent oxidation or other deterioration of the surface which might result in blows when molten metal comes in contact with the chills.

Chill Coils
Chills made of steel wire formed into helical coils or spirals.

Chill Nails
Chills in the form of nails.

Chill Test
Method of determining the suitability of a gray iron for specific castings through its chilling tendency, as measured from the tip of a wedge-shaped test bar.

Chill Zone
Area of a casting in which chilling occurs, as long sharp edges or exterior corners.

Chilled Iron
Cast iron poured against a chill to produce a hard, un-machinable surface.

Chip (verb)
To remove extraneous metal from a casting with hand or pneumatically operated chisels.

Chlorination
A refining or degasification process, wherein dry chlorine gas is passed through molten aluminum-base and magnesium-base alloys to remove entrapped oxides and dissolved gases.

Choke
Restriction in the gating system that controls the flow rate of metal into the mold cavity. See Cavity, Mold Cavity.

Choke or Primary Choke
The part of the gating system that most restricts or regulates the flow of metal into the mold cavity. See Cavity, Mold Cavity.

Chromel
A 90Ni - 10Cr alloy used in thermocouples.

Chromite
FeCr2O4. Specialty sand used in molding, has a similar effect to chills.

Chromium
Alloying element used as a carbide stabilizer. See Ferrochromium.

Chvorinov's Rule
A rule which states that solidification time is proportional to the square of the volume of the metal and inversely proportional to the square of the surface area, or t (solidification time)=KV2/SA2.

Clamp
A device for holding parts of a mold, flask, corebox, etc., together.

Clamp-Off
Indentation on a casting surface due to displacement of sand in the mold.

CLAS
A casting process in which metal fills the mold through the drag by application of a vacuum. See Drag.

Clay Wash
Clay and water mixed to a creamy consistency.

Clay, Refractory
A clay which, in addition to its capability of resisting high temperatures, also possesses strong bonding power.

Cleaning
Process of removing sand, surface blemishes, runners, risers, flash, surplus metal, and sand etc., from the exterior and interior surfaces of castings. Includes degating, tumbling or abrasive blasting, grinding off gate stubs, etc. See Runners, Risers, Flash, Surplus Metal, and Sand.

Close Over
The operation of lowering a part of the mold over some projecting portion such as a core.

CMM
Abbreviation for Coordinate Measuring Machine.

Computerized Numerical Control (CNC)
The use of computers and software to control metal cutting machines. Cutting tool paths can be generated directly from CAD produced part drawings. See Computer Aided Design (CAD).

Coalescence
Agglomeration of fine particles into a mass. Also growth of particles of a dispersed phase by solution and reprecipitation. Also grain growth by absorption of adjacent undistorted grains.

Cobalt
Blue-white metal, melting at 2,715°F (1,492°C), used in very hard alloy such as stellite, and a binder in carbide cutting tools. See Alloy, Stellite.

Cobalt 60
A radioactive isotope of the element cobalt used in radiographic examinations of castings, and for determining height of molten metal in cupola well. It is aslo used in used in medical and industrial radiography. See Cupola.

Cocoon Process
A method of protecting metal parts by spraying on a cover of plastic filaments.

Code Holes
The information holes in perforated tape, as opposed to feed or sprocket holes.

Coefficient of Expansion

Unit increase in size resulting from a unit increase in temperature; measured in inches per inch per degree Fahrenheit (in/in/1/2°F) or in millimeter per millimeter per degree Celsius (mm/mm/1/2°C).

Coercive Force
The magnetizing force that must be applied in the direction opposite to that of the previous magnetizing force in order to remove residual magnetism; thus, an indicator of the strength of magnetically hard materials.

Cohesion

The force by which like particles are held together. It varies with different metals and depends upon molecular arrangement due to heat treatment.

Coining
A process of straightening and sizing castings by die pressing. See Castings.

Coke
Coal derivative resulting from the distillation of bituminous coal in the absence of air. The distillation process removes all of the volatile material from the coal so it can be used as a very intense source of fuel in cupola melting. Source of some carbon found in iron.

Coke Bed
First layer of coke placed in the cupola. Also the coke used as the foundation in constructing a large mold in a flask or pit.

Coke Breeze
Fines from coke screening, used in blacking mixes after grinding; also briquetted for cupola use.

Coke Furnace
Type of pot or crucible furnace using coke as the fuel. See Coke, Crucible Furnace.

Coke Porosity
The percentage volume of cell space in coke.

Coke, Beehive
Coke produced from a bituminous coal by the beehive process where heat for the coking process comes from a partial combustion of the coke. Generally characterized by an elongate stringy structure.

Coke, By-Product
Coke produced from bituminous coal in airtight code ovens where heat for coking process is externally applied. Generally more uniform in size than beehive coke, and usually ball or cube shape.

Coke, Petroleum
Residue left from the distillation of petroleum crude, used as a carbon raiser.

Cold Blast Pig Iron
Pig iron produced in a blast furnace without the used of the heated air blast. See Pig Iron.

Cold Box Process
A rapid coremaking process which does not require application of heat to cure the cores. Hardening of the cores is accomplished by chemical reaction rather than by conventional baking. A phenolic resin is added to the sand used to make the core. This resin reacts chemically when exposed to an accelerator, typically an active organic gas, and hardens very quickly, forming an organic bond in the core sand. This reaction occurs at room temperature and does not require special coreboxes or equipment. Additionally, since the bond is organic, the sand collapses readily during shakeout and can be recovered easily from the casting.

Cold Chamber Machine
A diecasting machine where the metal chamber and plunger are not immersed in hot metal.

Cold Chamber, Club Sandwich, Two-Faced, Three-Piece Die
A diecasting die in which two different pieces are cast in two widely separated cavities.

Cold Cracking
Cracks in cold or nearly cold metal due to excessive internal stress caused by contraction. Often brought about when the mold is to hard or casting is of unsuitable design.

Cold Lap
Wrinkled markings on the surface of an ingot or casting from incipient freezing of the surface. See Ingot, Casting.

Cold Setting Binders
Term used to describe any binder that will harden the core sufficiently at room temperature so core can be removed from its box without distortion; commonly used in reference to oil-oxygen type binders. See Binder.

Cold Setting Process
An of several systems for bonding mold or core aggregates by means of organic binders, relying upon the use of catalysts rather than heat for polymerization (setting).

Cold Short
A characteristic of metals that are brittle at ordinary or low temperatures.

Cold Shortness
Brittleness when metal is at a low temperature.

Cold Shot
Small globule of metal embedded in but not entirely fused with the casting.

Cold Shut
A surface imperfection due to unsatisfactory fusion of metal. It is caused by insufficient fluidity, low pouring temperature, improper choice of alloy, or inadequate runner systems. The location where two streams of metal do not unite thoroughly in a casting. It may have the appearance of a crack or seam with smooth, rounded edges. Also see Cold Lap.

Cold Work
Plastic deformation of a metal at room temperature. Substantial increases in strength and hardness may occur.

Cold-Box Process
Any core binder process that uses a gas or vaporized catalyst to cure a coated sand while it is in contact with the core box at room temperature.

Collapsibility
Tendency of a sand mixture to break down under conditions of casting.

Collapsible Sprue
A sprue pattern of flexible material, or of spring-tube design, used in squeeze-molding of plated patterns, and incorporating a pouring cup. See Pattern, Sprue, Pouring.

Collimator
A device for confining the elements of a beam of radiation within an assigned solid angle.

Colloidal Clay
Finely divided clay of montmorillonite, kaolinite, or illite class; prepared for foundry purposes as in sand bonding.

Colloids
Finely divided material, less than 0.5 micron, 0.00002 in., in size, gelatinous, highly absorbent, and sticky when moistened.

Colloids, Colloidal Material
Finely divided material less than 0.5 micron, 0.00002 in., in size, such as albumin, glue, starch, gelatin, and bentonite.

Coloimetric Analysis
Determining the amount of an element in a solution by measuring the intrinsic color.

Color Etching
A micro-etch resulting from the formation of a thin film of a definite compound of the metal.

Columnar Structure
Coarse structure of parallel columns of grains caused by highly directional solidification resulting from sharp thermal gradients.

Combination Die
A die-casting die having two or more cavities of dissimilar parts. See Multiple-Cavity Die.

Combined Carbon
The carbon in iron or steel combined with other elements and therefore not in the free state as graphite or temper carbon.

Combined Water
That water in mineral matter which is chemically combined and driven off only at temperatures above 231°F (111°C).

Combustibles
Materials capable of combustion; inflammable.

Combustion
Chemical change as a result of the combination of the combustible constituents of the fuel with oxygen, producing heat.

Combustion Chamber
Space in furnace where combustion of gaseous products from fuel takes place.

Combustion Efficiency
The amount of heat usefully available divided by the maximum amount which can be liberated by combustion; usually expressed in percentage.

Comfort Zone (Average)
The range of effective temperature over which the majority (50% or more) of adults feel comfortable.

Comodizing
A rust-proofing process for steel.

Compacted Graphite Iron
An iron with with elongated graphite particles with rounded edges and roughened surfaces. It possesses characteristics of both gray and ductile iron. See Gray Iron, Ductile Iron.

Composite Construction
Welding a steel casting to a rolled or forged steel object or to another casting. See Cast-Weld.

Compression Test
Imposing a dead load on a small cylindrical test piece to determine compressive strength, expressed in pounds per square inch.

Compressive Strength
The maximum compressive strength which a material is capable of developing.

Compressor
Device for providing gas under pressure. Usually connotes high pressures and not so high volume.

Compressive Strength (Yield)
The maximum stress in compression that can be withstood without plastic deformation or failure.

Contact Cement
Patternmaking bonding technique, in which liquid bonding agent is painted on both surfaces to be joined and allowed to dry. These dry surfaces placed in contact adhere firmly.

Condensing Rings
A special form of chill used for cast iron to produce a dense but graphite structure. See Cast Iron.

Conduction
The transmission of heat, sound, etc. by the transferring of energy from one particle to another.

Conductivity
The quality or power of conducting or transmitting heat, electricity, etc.

Conductivity (Thermal)
The quantity of heat that flows through a material measured in heat units per unit time per unit of cross-sectioned area per unit of length, (electrical) the quantity of electricity that is transferred through a material of know cross-section and length.

Connor Gate (Runner) (Lip feeder)
A runner in which the feed block overlaps the casting by 1/16 in. (1.6 mm). See Runner.

Constant Intensity Pyrometer
Use of a comparison lamp filament's glow to estimate metal temperature.

Constantan
An alloy of nickel and copper use in thermocouples.

Constituent
A micrographically distinguishable part of an alloy or mixture.

Consumer's Risk
The risk the consumer runs of accepting lots of quality p2. See P2.

Contact Printing (Ink Print)
A method of recording details of a macroetched structure. See Sulfur Prints.

Contamination
The presence of small percentages of deleterious elements in an alloy adversely affecting the alloy's mechanical properties and/or casting soundness.

Continous Tapping
A furnace or holding ladle that is made of discharge molten metal continuously during normal operation.

Continuous Annealing Furnace
Furnace in which castings are annealed or heat treated by being passed through different zones kept at constant temperatures. See Annealing.

Continuous Desulfurization
A process of removing sulfur from molten ferrous alloys on a continuous basis.

Continuous Mixer
Used to continuously mix chemically bonded sand.

Continuous Phase
The phase that forms the matrix or background in which the other phases are present as isolated units.

Controlled Area
A defined area in which the occupational exposure of personnel to radiation or to radioactive material is under the supervision of an individual in charge of radiation protection.

Contraction
Decrease in size or volume due to cooling of the metal after it is poured. Shrinkage is the term applied to the decrease in volume of a metal from liquid to solid stage. Contraction immediately follows shrinkage.

Contraction Cracks
Cracks formed by restriction of the metal while contracting in the mold; may occur just after solidification, called a hot tear, or a short time after the casting has been removed from the mold. See Hot Tea.

Contraction Rule
See Shrinkage, Patternmaker's.

Controlled Atmosphere
Any gas or mixture of gases that prevents or retards oxidation and decarburization.

Controlled Cooling
Process by which a metal object is cooled from an elevated temperature in a predetermined manner of cooling to avoid hardening, cracking, or internal damage.

Convection
The motion resulting in a fluid from the differences in density. In heat transmission, this meaning has been extended to include both forced and natural motion or circulation.

Converter
Vessel for refining molten metal by blowing a gas, usually air, through it. Used in making steel from molten cast iron and in refining copper. See Cast Iron.

Conver, Vibratory
A materials-handling device used usually with shakeout operations, to help clean sand from the castings as they are moved from one place to another in the foundry and as a feeding device to regulate materials flow. Operations with vibrational energy.

Conveyor
A mechanical apparatus for carrying or transporting materials from place to place. Types include apron, belt, chain, gravity, roller, monorail, overhead, pneumatic, vibrating, etc.

Conveyor Belt
A continuously moving belt used in an automated or semiautomatic foundry to move materials from one station to another. See Conveyor.

Conveyor Screw
Rotary worm-type blade used to move materials in automated core and mold making and other continuous sand-mixing operations.

Conveyor, Pallet
A materials-handling device that holds one or more molds and transports them from the molding station through pouring to shakeout. See Conveyor.

Conveyor, Pneumatic Tube
An air-tube means of moving materials from on place to another, primarily orders, light metal samples, and sand and other finely divided materials, as bentonite.

Conveyor, Roller
A line of conveyance in an automated or semiautomated foundry which employs a series of steel roller for moving objects.

Conveyor, Slat
A materials-handling device built on a continuous belt of metal slats that moves granular materials and castings throughout a foundry. See Conveyor.

Cooler
The largest of three water coolers surrounding the cinder notch of a blast furnace.

Cooling Curve
A curve delineating the relationship between temperature and time during the cooling of a metal or alloy test specimen. Since most phase changes involve evolution or absorption of heat, there may be abrupt changes in the slope of the curve. See Cracking Strip.

Cooling Stress
Stresses developed by uneven contraction or external constraint of metal during cooling.

Cooling, Controlled
A process of cooling from an elevated temperature in a predetermined manner used to produce a desired microstructure to avoid hardening, cracking or internal damage.

Cope
The top half of a horizontally parted mold. The upper or topmost section of a flask, mold, or pattern. See Flask, Mold, Pattern.

Cope, False
Temporary cope used only in forming the parting and therefore not a part of the finished mold. See Cope.

Coping Out
The extension of sand of the cope downward into the drag, where it takes an impression of a pattern. See Drag.

Copper
For foundry applications, copper is meant to include all alloys containing 98% or more copper. Used for conductivity castings. Melting point 1,083°C (1,981.4°F).

Copper, Electrolytic
Copper produced by the electrolysis method.

Corbel
One or more projecting courses of brick each projecting beyond the course below.

Core
A bonded sand insert placed in the mold to form an undercut or hollow section in the casting which cannot be shaped by the pattern. A core is frequently used to create openings and various shaped cavities in the casting. The shaped body of sand which forms interior of casting and also selected external features.

Core Arbor
An iron framework embedded in a large core to stiffen it and for convenience in handling.

Core Assembly
A complex core made from a number of cores or sections.

Core Barrel
Pipe-shaped device upon which a cylindrical core is formed.

Core Binder
Any material used to hold the grains of core sand together.

Core Blow
A gas pocket in a casting adjacent to a core cavity caused by entrapping gases from the core.

Core Blowing Machine
Machine which reams the core by blowing sand into the core box. See Core, Core Box.

Core Box
A mold in which a core is formed. A wood, metal or plastic box, whose cavity has the shape of the desired core which is to be made therein. See Core, Mold.

Core Box, Combination
Core box and core dryers from the same pattern. One half is used as a half core box and a core drier. See Core Box, Pattern.

Core Branch
Part of a core assembly. See Core Assembly.

Core Breaker
A machine for crushing cores or for removing cores from castings.

Core Cavity
The interior form of a core box that gives shape to the core. Also, the cavity produced in a casting by use of a core. See Core Box.

Core Collapsibility
The rate of disintegration of the core at elevated temperature.

Core Compound
A commercial mixture used as a binder in core sand. See Binder, Core Sand.

Core Crab
An iron framework embedded in a large core to stiffen it and for convenience in handling.

Core Crack
Appears in a casting after solidification and cooling due to excessive strain generally resulting from nonuniform cooling.

Core Density
Either the permeability of core or the weight per unit volume.

Core Driers or Dryers
Supports used to hold cares in shape while being baked; constructed from metals or sand for conventional baking, or from plastic material for use with dielectric core-baking equipment. See Dielectric Baking.

Core Extruder
A special shell-core-making machine that produces a continuous length of cores, usually of cylindrical cross-section.

Core Filler
Material used in place of sand in the interiors of large cores -coke, cinder, sawdust, etc., usually added to aid collapsibility.

Core Fin
A casting defect, a depression in the casting caused by a fin on the core that was not removed before the core was set, or by paste that has oozed out from between the joints.

Core Float
A casting defect caused by core movement towards the cope surface of the mold, as a result of core buoyancy in liquid steel, resulting in a deviation from the intended wall thickness.

Core Frame
Frame of skeleton construction used instead of a complete core box in forming intermediate and large cores. See Core Box.

Core Grinder
Machine for grinding a taper on the end of a cylindrical core or to grind a core to a specified dimension, usually flat face.

Core Gum
A pitch material used as a core binder. See Core Binder.

Core Hardness
The ability of a core to resist scratching or abrasion.

Core Jig (Fixture)
Device in which a number of cores are assembled outside the mold, then used to locate the assembly in the proper position in the mold.

Core Knockout Machine
A mechanical device for removing cores from castings. See Core, Casting.

Core Lightener
A core material of any size and shape used to lighten pattern castings and match plates.

Core Machine
Machine for making cores. See Core.

Core Maker
A core seat shaped or arranged that the core will register correctly in the mold; also termed locator, indicator, register, telltale. A core maker is also a person who makes cores.

Core Mud
A daubing mixture used to correct defect in cores. See Core.

Core Oil
Linseed-base or other oil used as a core binder. See Core Binder.

Core Oven
An oven for baking cores.

Core Paste
Material in paste form used as an adhesive to join sectional cores.

Core Plate
A plate or board made of metal or heat-resisting material on which certain types of cores are baked.

Core Print
Projections on a pattern that form and locate cores in a mold. A core print is also a projection on the core or an area in the mold for same purpose.

Core Refractiveness
The ability of a core to resist breakdown when exposed to heat.

Core Rod
Steel rods imbedded in a core used to reinforce the core and strengthen it. See Core.

Core Sand
Sand for making cores to which a binding material has been added to obtain good cohesion and permeability after drying. Core sand is usually low in clays.

Core Sand Mixer
Equipment in which cores are made. See Core.

Core Setter
An operator or machine for placing cores in molds.

Core Setting Jig
A device used to help set and position a core into the mold.

Core Shift
A dfect resulting from the movement of the core from its proper position in the mold cavity. A variation from specified dimensions of a cored section due to a change in position of the core or misalignment of cores in assembling.

Core Shooter
A device using low air pressure to fluidize the sand mix which is released quickly in such a way as to force it into a core box. See Core Box.

Core Spindle
A shaft on which a core barrel is rotated in making cylindrical cores.

Core Sprayer
A device for spraying a coating on cores. See Core.

Core Stickle Template (Sweep)
Device of wood or metal to give shape to certain types of cores or molds.

Core Strainer (Strainer Tub)
Baked sand or refractory disc with uniform size holes through its thickness used to control the discharge of metal from pouring basins into sprues or to regulate the flow of metal in gates systems of molds; also to prevent entrance of dross or slag into the mold cavity.

Core Truck
Truck or carriage used for transporting cores.

Core Vents
A wax product, round or oval in form, used to form the vent passage in a core. Also refers to a metal screen or slotted piece used to form the vent passage in the corebox employed in a core blowing machine.

Core Wash
A suspension of a refractory material applied to cores and dried. Intended to improve the surface finish of the casting. A refractory coating for a core.

Core Wires Or Rolls
See Core Rod.

Core, Ram-Up
Core attached to the pattern and rammed up in the mold, where it remains when the pattern is withdrawn.

Core-Baking Dielectric
Heating cores to baking temperatures by means of high-frequency dielectric equipment; particularly adapted to thermo-setting resin core binders. See Core, Dielectric Baking.

Corebox
See Core Box.

Coreless Induction Furnace
See Induction Furnace.

Core-Making Machine
A device to make cores. See Core.

Coremaker
A craftsman skilled in the production of cores for foundry use.

Coreprint
A projection on a pattern which leaves an impression in the mold for supporting the core. See Core, Pattern.

Corer, Sag
A decrease in the height of a core, usually accompanied by an increase in width, as a result of insufficient green strength of the sand to support its own weight.

Coreroom
Department of the foundry in which cores are made.

Coring (Metallurgical)
Variable composition due to the solidification characteristics of an alloy. Typically these compositional differences occur on a micro scale, the distances between compositional extremes being controlled by the solidification structure of the alloy.

Coring Up
Placement of cores chills, and chaplets in mold halves before closing the mold. See Chaplets.

Cornerslick (inside and outside corners)
A molder's tool used for repairing and slicking the sand in molds. Used primarily on dry sand and loam.

Corrective Effective Temperature Chart
A chart on which information can be plotted resulting in an adjustment temperature reading more indicative of human comfort.

Corrosion
Gradual chemical or electrochemical attack on a metal by atmosphere, moisture or other agents. A chemical attack of furnace linings by gases, slags, ashes or other fluxes occurring in various melting practices.

Corrosion Index
A number expressing the maximum depth in mils to which corrosion would penetrate in one year on the basis of a linear extrapolation of the penetration occurring during the lifetime of a given test or service.

Corrosion Wear
Wear in which chemical or electrochemical reaction with the environment is significant.

Corundum
Native alumna, or aluminum oxide, Al2O3, occurring as rhombohedral crystals and also in masses and variously colored grains. Applied specifically to nontransparent kinds used as abrasives. It is hardest mineral except the diamond. Corundum and its artificial counterparts are abrasives especially suited to the grinding of metals.

Coslettizing
Producing a black, rust-resisting surface on iron and steel by boiling for some hours in water containing phosphoric acid and iron filings.

Cottrell Process
An electrostatic method of removing solid particles from gases.

Count rate meter
A device which gives a continuous indication of the average rate of ionizing events.

Couple
Two dissimilar conductors in electrical contact. An electromotive force in created under proper electrolytic influences or during heating.

Courses
Alternate layers of material in a pattern, or brickwork.

Cover
A protective blanket laid on a melt to exclude oxidizing atmosphere and in the case of magnesium to prevent its igniting. Neutral covers simply protect metal from atmosphere; reacting covers contain an agent such as a deoxidizer.

Cover Core
A core set in place during the ramming of a mold to cover and complete a cavity partly formed by the withdrawal of a loose part of the pattern. Also used to form part or all of the cope surface of the mold cavity. A core placed over another core to create a flat parting line. See Core, Mold Cavity, Pattern.

Cover Half
In Die casting, the stationary half of the die.

Crack, Hot
Developed in a casting before it has cooled completely, and usually due to some part of the mold restraining solid contraction of the metal. See Tear, Hot Tear.

Crack, Hot Tear
A rupture occurring in a casting at or just below the solidifying temperature by a pulling apart of the soft metal, caused by thermal contraction stresses. See Quench Crack.

Cracking Strip
A fin of metal molded on the surface of a casting to prevent cracking. See Fin, Cooling Curve.

Crane
A machine for lifting heavy weights; may be hand or power operated. Type include electric, gantry, jib, monorail, etc.

Crane, Gantry
A bridge carrying a traveling crane and supported by a pair of trestles running on parallel tracks.

Crane, Jib
A crane suspended from a jib.

Crane, Mobile
A crane supported on structure that rolls on wheels; may be moved manually or by its own power.

Crane, Wall Jib
A jib crane mounted on a wall rather than on an overhead beam.

Craze Crack (Crazing)
Minute crack on ceramic or refractory surface caused by thermal or mechanical shock.

Crazing (Worming)
A defect found in pack-hardened tools, manifested in surface markings.

Creep
Time rate of deformation continuing under stress intensities well within the yield point, proportional limit, or the apparent elastic limit for the temperature.

Creep Limit
The maximum stress that will result in creep at a rate lower than an assigned rate. See Creep.

Crib
Network of cast iron used to support the cope when no cope flask is used.

Cristobalite
Simplest crystallographic form of SiO2.

Critical Cooling Rate
The minimum rate of continuous cooling just enough to prevent undesired transformations.

Critical Points (Temperatures)
Temperatures at which changes in the phase of a metal talk place, and are determined by the liberation of heat when the metal is cooled and by the absorption of heat when the metal is heated, resulting in halts or arrests on cooling and heating curves.

Critical Shear Stress
The shear stress required to cause slip in a single crystal, in a designated slip direction on a given slip plane. Referred to as the critical resolved shear stress if the shear stress reaches a threshold level.

Critical Strain
A term used in stress corrosion cracking tests to indicate the maximum strain rate necessary to promote stress corrosion cracks.

Croning Process (C Process, Cronizing)

A casting process name after its German developer Johannes Croning. It is a precision production process using a phenol formaldehyde resin binder. See Shell Molding.

Cross Section
A view of the interior of an object that is represented as being cut in two, the cut surface presenting the cross section of the object.

Crossbar
Wood or metal bar placed in a flask to give greater anchorage to the sand than is afforded by its four walls.

Crown
Furnace roof, especially when dome-shaped; highest point of an arch.

Crucible
A ceramic pot or receptacle made of materials such as graphite or silicon carbide, with relatively high thermal conductivity, bonded with clay or carbon, and used in melting metals; sometimes applied to pots made of cast iron, steel, or wrought steel. The name derives from the cross, the Crux, with which ancient alchemists adorned it. See Cast Iron.

Crucible Furnace
A furnace fired with coke, oil, gas, or electricity in which metals are melted in a refractory crucible. See Coke, Crucible.

Crucible Zone
The zone in the cupola between the bottom and the tuyere. See Cupola, Tuyere.

Crush
A casting defect, such as buckling or breaking, of a section of mold due to incorrect register when closing. Also, an indentation in the casting surface due to displacement of sand in the mold when the mold is closed.

Crush Strip Or Bead
An indentation in the parting line of a pattern plate which ensures that cope and drag have good contact by producing a ridge of sand which crushes against the other surface of the mold or core.

Crushing
The pushing out of shape of core or mold when two parts of the mold do not fit properly.

Crystal
A physically homogeneous solid in which the atoms, ions, or molecules are arranged in a three-dimensional repetitive pattern.

Crystal Analysis
Determination of crystal structure.

Crystal Lattice
The way atoms are arranged in a crystal. Spacewise, there are only 14 different lattices.

Crystalline Fracture
Fracture of a brittle metal, showing definite crystal faces in the fractured surface.

Crystallization
Act or process of forming crystals or bodies formed by element or compounds solidifying so they are bounded by plane surfaces, symmetrically arranged, and are the external expressions of definite internal structure.

Cumulative Trauma Disorder (CTD)
Illnesses that develop gradually over time and involve disorders of the soft tissues of the body. Caused or aggravated by repeatedly or constantly applied excessive forces, awkward postures, or highly repetitive movements of the body.

Cupola
A cylindrical straight shaft furnace usually lined with refractories, for melting metal in direct contact with coke by forcing air under pressure through openings near its base. Vertical shaft furnace lined with refractories used to produce cast iron by high temperature melting of metallic and mineral charge materials. See Tuyere.

Cupola Blower
A machine which compresses a large volume of air at low pressure for operation of the cupola.

Cupola Dust Arrester
A device attached to the stack of a cupola which removes dust and sparks for the outgoing gases. See Cupola.

Cupola, Basic
Cupola with refractory lining which has a basic reaction, usually magnesite, and is operated with slags high in lime. Lining may be neutral material like carbon, used with high lime slags. See Cupola, Slag.

Cupola, Hot Blast
Cupola in which the air blast is heated to temperatures from 400° to 1,000°F.

Cupola, Water-Cooled
Cupola in which the melting zone and tuyeres are cooled with water. Cooling of melting zone may be internal through jackets or steel tubing under the refractory lining. Cooling is also accomplished externally by water flowing down the outer shell. See Cupola.

Curing Time (No Bake)
That period of time needed before a sand mass reaches maximum hardness.

Cut
Defect in a casting resulting from erosion of the sand by metal flowing over the mold or cored surface. See Casting.

Cutoff Machines, Abrasive
A machine using a thin abrasive wheel and employed in cutting off gates and risers from casting or in similar operations. See Abrasive.

Cuts
Defects in castings resulting from erosion of the sand by the molten metal pouring over the mold or core surface. See Casting.

Cutter, Gate
A piece of sheet metal or other tool for removing a portion of the sand in a mold to form the gate or metal entrance into the casting cavity. A scoop or other form of cutting gates in the mold. See Gate.

Cutter, Sprue
A piece of metal tubing or other tool used to remove a portion of the sand from a mold to form the sprue or passage from the exterior of the mold to the gate. Also a machine used for shearing sprues and gates from castings. See Gate, Sprue.

Cutting Wheel
The plastic discs impregnated with an abrasive for cutting ceramics and metals. Used on abrasive cutoff machines.

Cyclone (Centrifugal Collector)
In air pollution control, a controlled descending vortex created to spiral objectionable gases and dust to the bottom of a collector core.

Cyclonic Scrubber
In air pollution control, radial liquid (usually water) sprays introduced into cyclones to facilitate collection of particles.

Cyclotron
A device for accelerating charged particles to high energies by means of an alternating electric field between electrodes placed in a constant magnetic field.

D (Fordath) Process
Shell molding in which the shell is made by blowing sand into a box like heated structure so that a shell of controlled thickness is created. See Shell Molding.

Damping Capacity
The ability to absorb vibration. More accurately defined as the amount of work dissipated into heat by a unit volume of material during a completely reverse cycle of unit stress.

Datum Plane
In layout and machining operations the reference plane from which dimensions are measured in the perpendicular direction.

Datum Points
In layout and machining operations the reference points on a datum plane from which dimensions are measured.

Daub
To coat or plaster the inside of a cupola at the melting zone or the inside of a ladle with a refractory mixture.

Daubing
Filling of cracks in molds or cores by specially prepared pastes or coatings to prevent a mechanical penetration of metal into these cracks during pouring. Also, the final plastering or coating of the cupola or ladle after shrinkage has taken place during the drying period. Clay slurry or clay wash with various coating compounds are applied. See Clay Wash.

DC (Direct Chill) Casting
A continuous method of making ingots or billets or extrusion by pouring the metal into a short mold. Some times called semi-continuous casting.

Dead Steel
Fully killed steel, also applied to steel which fails to respond to heat treatment. See Heat Treatment, Killed Steel.

Deadburned
Term applied to refractory materials obtained by calcimining at a temperature high enough to form a product inert to atmospheric moisture and carbon dioxide, and less apt to contract. See Refractory.

Deadburned Dolonite
Dolonite burned at high temperature with additions of an agent, such as oxide of iron.

Deadhead
The useless metal projecting on a casting which corresponds to the position of a riser in the mold. See Casting, Riser.

Decant
Pour from one vessel to another. Pour off molten metal without disturbing the sludge.

Decarburiztion
Loss of carbon from the surface of a ferrous alloy as a result of heating in a medium, usually oxygen, that react with carbon.

Decibel (dB)
Unit for measuring the ration amounts of acoustical power; one-tenth of a bel.

Deep Etching
Macroetching; etching for examination at a low (less that 10X) magnification, in a reagent that attacks the metal to a much greater extent than normal for microscopic examination. Gross features may be developed; i.e., abnormal grain size, segregation, cracks, or grain flow.

Deep Red Filter
A gas filter in air pollution control, consisting of a loosely packed mat of fibrous materials; not practical where high grain loading are encountered.

Defect
A discontinuity in the product whose severity is judged unacceptable in accordance with the applicable product specification.

Deformation test
An AGS test using an instrument such as the Dietert Universal Sand-Strength Testing machine (with deformation accessory) to determine the amount in inches that the sand specimen is compressed before it ruptures.

Degasifier
A material employed for removing gases from molten metals and alloys.

Degassing
Usually a chemical reaction resulting from a compound added to molten metal to remove gases from the metal. Often inert gases are used in this operation.

Degassing Flux
A flux for removing gas from the melt.

Degree of Ramming
The extent of hardness to which a sand mold is rammed. See Ramming, Sand Molding.

Delay Screen (Skim gate (Erroneously), Skim Strainer)
A small piece of perforated light gage tinned sheet steel, or of copper, aluminum, and/or magnesium alloys, frequently placed in the pouring basin at the top of the downsprue. It delays the flow of metal long enough to allow the basin to fill before it melts to permit only clean metal from the bottom of the basin to enter the downsprue. Delay screens are also use elsewhere in the gating system.

Delta Iron
An allotropic (polymorphic) form of iron, stable above 2550°F, crystallizing in the body-centered-cubic lattice.

Dendrite
A crystal of branched appearance, formed during solidification of alloys, the branching habit being controlled by specific crystallographic directions with the branching structure resembling a a fir tree.

Densitometer
Instrument utilizing the photoelectric principle to determine the degree of darkening of developed photographic film.

Density
The mass per unit volume of a substance, usually expressed in grams per cubic centimeter or in pounds per cubic foot.

Density (Photographic)
Density is used to denote the degree of darkening of photographic film. Logarithm of opacity of exposed and processed film. Opacity is the reciprocal of transmission; transmission is the ratio of transmitted to incident intensity.

Dephosphorization
Elimination of phosphorus from molten steel.

Dermatis
An inflammation of the skin, which may be caused by allergy to certain casting adjuncts, as resins; particularly in the shell process.

Descale
Remove the fire scale from the surface of casting. See Casting.

Design Base Line
The noise spectrum which is the goal of any particular noise reduction program.

Designations
Type of metal named, as steel, malleable, nonferrous, etc.

Despersion Hardening
Hardening by the formation of hard microconstituents dispersed in a softer matrix. See Precipitation Hardening.

Desulfurization
Removal of sulfur from the molten metal by addition of suitable compounds.

Desulfurizer
A material used to remove sulfur from molten metals and alloys. Also, a form of holding ladle or basin in which the molten metal and desulfurizing material are brought into contact. See Ladle.

Detroit Cup Test
A cupping test for sand, using a steel ball as plunger, the depth of cup being shown on a dial.

DeVries Test
A test to give the relative hardness of deep hardening steels. See BHN, Brinell Hardness.

Dew Point
The temperature at which moist air will become saturated and condensation of water vapor will take place.

Dewaxing
The process of melting out the expendable was pattern from an investment mold by the application of heat, usually at temperatures less than 250°F (121°C).

Dexidation
Removal of excess oxygen from molten metal, usually accomplished by adding materials with a high affinity for oxygen, the oxides of which are either gaseous or readily form slags.

Dextrin
Soluble gummy carbohydrate formed by the decomposition of starch by heat, acids, or enzymes; it is use din core compounds, mold compounds, mold washes, core pastes, and other compounds requiring high dry compressive strengths.

Dezincification
Corrosion of some copper-zinc alloys, involving loss of zinc and the formation of a spongy porous copper. See Alloy.

Diameters
In microscopy, an indication of the amount of magnification. 1000 diameters = 1000 times original size.

Diammonium Phosphate
Used to fireproof clothing of foundry workers.

Diaphragm Shell Molding Machine
An arrangement for applying a squeeze pressure with a high-temperature silicone rubber diaphragm.

Diaspore Clay
A rocklike mineral consisting chiefly of diaspore (HAlO2) bonded by fire clay substance with an alumina content higher than 63%.

Dia-Tester (Wolpert Hardness Tester)
A hardness testing machine using the Vickers or Brinell ball indenter. See BHN, Brinell Hardness, Vickers Diamond.

Diathermometer
An instrument for examining the thermal resistance or the heat conducting power of objects.

Diatomaceous Earth (Infusorial Earth)
A hydrous of silica which is soft, light in weight and consists mainly of microscopic shells of diatoms or other marine organisms.

Die
A metal block used in forming materials by casting, molding, stamping, threading, or extruding. A metal form used as a permanent mold for die casting or lost wax process. See Lost Wax Process.

Die Assembly
The parts of a die stamp or press that hold the die and locate it for the punches.

Die Casting
(a) Forcing molten metal into permanent molds, dies. Die Casting is also called Pressure Casting. See Pressure Die Casting. (b) noun Casting resulting from die-casting process. (c) verb Pouring molten metal under pressure into metal molds.

Die Casting, Cold Chamber
Type of casting made in a die-casting machine in which the metal injection mechanism is not submerged in the molten metal.

Die Casting, Hot Chamber
Type of casting made in a die-casting machine in which the metal injection mechanism is submerged in the molten metal.

Die Coating
See Release Agent.

Die Insert
A removable liner or part of a die body or punch.

Die Set
In stamping, the parts of the press that hold the die and locate it in proper relation to the punches.

Die Sinking
Forming or machining a depressed pattern in a die.

Dielectric Baking
Baking of cores and molds in a field of high-frequency electric current generated by dielectric equipment; employed with resin-bonded cores. See Bake, Baked Core.

Dielectric Oven (Dryer)
A rapid-drying high frequency electric oven used to bake cores. See Bake, Baked Core.

Dietert Process
A patented process for the production of precision molds involving blowing a contoured core around a pattern to form half a mold. See Core, Mold, Pattern.

Dietert Tester
A patented apparatus for the direct reading of a Brinell hardness after impression without using magnification or conversion tables. See BHN, Brinell Hardness.

Differential Heat Treatment
A heating process by which the temperature is varied within the object so that, after cooling, various parts may have different properties as desired. See Heat Treatment.

Diffuser
X-ray equipment, a portion of the condensing and focusing system that permits even distribution of energy. See X-Ray.

Diffusion
Movements of atoms within a solution. Net movement is usually from regions of high concentration to regions of low concentration to achieve homogeneity of the solution which may be a solid, gas, or liquid.

Dike
A patented flexible seal to prevent blow-by in core boxes. See Core Box.

Dilatometer
Instrument for measuring expansion or contraction, the length of a metal sample, caused by changes in temperature or structure.

Dimensional Stability
Ability of a casting to remain unchanged in size and shape under ordinary atmospheric conditions.

Dimensional Tolerance Grades
A system of classifying the tightness of tolerances for the purpose of defining accurately the tolerances involved, and for simplifying the communication process between customer and producer regarding what is wanted, and what is possible, respectively.

Dip Coat
In solid and shell mold investment casting, a fine ceramic coating applied as a slurry to the pattern to produce maximum surface smoothness, followed by a cheaper conventional investment. See Investment Precoat.

Dip Tank
A tank, preferably lined with rubber, epoxy, or other nonmetallic, into which die castings are dipped for cooling after leaving the machine.

Dipped Joint
A thin joint made by dipping of the brick in a thin mortar.

Direct Casting
Teeming from the ladle into the casting mold without the use of a tundish.

Direct-Arc Furnace
Electric furnace in which the material is heated directly by an arc established between the electrodes and the work. See Dielectric Furnace.

Directional Solidification
Refers to the arrangement of a solidification pattern in a casting by establishment of high temperature gradients, whereby solidification of the metal begins at the point farthest from the metal entrance or sprue and the metal progressively freezes or solidifies to and including the sprue. See Solidification.

Dirt
Indefinite term referring to any extraneous material entering a mold cavity and usually forming a blemish on the casting surface. See Mold Cavity.

Dirt Trap
A well employed in a gating system to entrap the first metal poured, which may contain dirt or unwanted particles (ineffective). See Slag Trap.

Dirty Casting
A casting containing an excessive amount of nonmetallic inclusions in the body of the metal. See Inclusion.

Disamatic Molding
Disamatic molding is a type of sand molding process in which molten metal is poured into a mold made of sand to make Gray Iron Castings. Disamatic machines are designed to provide molds built for vertical casting and the molds are created in a vertical orientation. Disamatic machines create flaskless molds. Disamatic molding gets its name from the company that manufactures the molding machine, DISA. A Disamatic molding machine is a vertically parted sand molding machine. The vertical molding machine is often the choice for production of very close tolerance Gray Iron Castings. See Gray Iron, Hunter Molding.

Disappearing Filament Pyrometer (Optical Pyrometer)
A telescope in which a hot body is viewed through an eyepiece and temperature is measured by the matching color of a calibrated lamp filament with color of hot metal.

Dispersed Shrinkage
Small shrinkage cavities dispersed through the casting, which are not necessarily cause for rejection. See Casting, Cavity, Shrinkage.

Dissolved Carbon
Carbon in solution in steel in either the liquid or solid state.

Distorted Pattern
A pattern untrue to the specified dimensions. See Pattern.

Distortion
See Warpage.

Distribond
A siliceous clay containing Bentonite used as bond in molding sands. See Molding Sands.

Distribution, Sand Grain
Variation or uniformity in particle size of a sand aggregate when properly screened by U.S. Standards screens.

Distruptive Strength
Maximum strength of a metal when subjected to three principal tensile stresses at right angles to one another and of equal magnitude.

Disturbed Metal
The cold worked metal formed on a polished surface during the processes of grinding and polishing.

Divorced Pearlite (Granular perlite, Spheroidite, Spheroidized cementite)
Pearlite in which the cementite has been spheroidized by prolonged annealing just below the Ac1 point, or by annealing at the same temperature after cold working. See Ac1, Pearlite.

Dolomite
A mineral calcium-magnesium carbonate (Ca, MG (CO3)2) used as a flux in iron melting and smelting; also as a base in refractors.

Dosimeter
Instrument used to detect and measure an accumulated dosage of radiation; in common usage it is a pencil-size ionization chamber with a built-in self-reading electrometer; used for personal monitoring. See Dosimeter, Pocket.

Dosimeter, Pocket
A pocket ionization chamber containing it own electrometer. An auxiliary charging device is usually necessary. See Dosimeter.

Double Annealing
As applied to hypoeutectoid steel, a process of heating to above the upper critical point, Ac3, and holding at that temperature until complete solution of the carbide has been achieved then cooling rapidly and reheating immediately to above A3 and slowly cooling. See Ac3, Annealing.

Double Impression Method
A way of determining approximate Brinell hardness by placing a hardened steel ball between a specimen of known hardness and the metal to be tested and pressurizing in an arbor press. See BHN, Brinell Hardness.

Double Skin (Bottom Splash, Ingot Shell, Plaster)
A defect consisting of a secondary layer of metal sometimes found on top-poured ingots. See Ingot.

Double Tempering
A retempering operation sometimes necessary for steel containing retained austenite which breaks down during cooling from the first tempering to form a new and hence untempered martensite.

Doublebruned
Deadburn; not be mistaken for two firing.

Dowel
A pin used between the sections of parted patterns or core boxes to locate and hold them in position, registering them correctly. See Core Box.

Downcomer
In air pollution control, a pipe for conducting bases down into a conditioner and subsequent cleaning.

Downgate
See Downsprue.

Downsprue (Sprue, Downgate)
The first channel, usually vertical, which the molten metal enters; so called because it conducts metal down into the mold.

Downtime
Time lost from normal casting activity, due to unscheduled interruptions.

Draft
The taper on vertical surfaces of a pattern which allows easy withdrawal of the pattern from a compacted sand mixture without distorting or tearing of the sand and without excessive rapping and tearing of the mold walls.

Draft, Pattern
See Pattern Draft.

Drag
Lower or bottom section of a mold, pattern or flask. See Mold, Pattern, Flask.

Draw
A term used to temper, to remove pattern from mold, as an external contraction defect on surface of mold.

Draw (verb)
To remove a pattern from a mold.

Draw Bar (noun)
A bar used for lifting the pattern from the mold. See Mold, Pattern.

Draw Peg
A wooden peg used for drawing patterns.

Draw Plate
A plate attached to a pattern to facilitate drawing of a pattern from the mold.

Draw Screw
A threaded rod with an eye screwed into a pattern to enable it to be drawn from the mold. See Mold, Pattern.

Draw Spike
A steel spike used to rap and draw a pattern from the sand; it is driven into the wood of the pattern, as opposed to a Draw Screw, which threaded.

Draw, Surface
Appearance of shrink on the upper surface of a casting. See Casting, Shrink.

Drawback
A part of the mold, made of green sand, which may be drawn back to clear overhanging portions of the pattern. It is rammed up on a plate or arbor so that it can be lifted away. See Arbor, Mold, Pattern, Ramming.

Drawing
Removing pattern from the mold or mold from pattern in production work. See Temper.

Dried Sand
Sand which bas been dried by mechanical dryer prior to use in core making.

Drier (Dryer)
A material, as alcohol ammonium nitrate, sodium perborate and manganese oleate, added to a core or mold mixture to remove or reduce the water content.

Drier-Core
Plates for supporting odd shaped cores during baking.

Drillings, Test
Chips, or small particles of metal removed from a test specimen for chemical analysis.

Drop (Dropout)
A casting defect caused by sand dropping from the cope or other overhanging section.

Drop Ball
A heavy weight, usually ball or pear shaped, dropped from a height to break large pieces of metal scrap. Also used to strengthen warp castings.

Drop Gate
A term for a pouring gate or runner leading directly into the top of the mold.

Drop Off or Drop Out
Sand falling from the Cope of a mold. See Drop.

Drop or Drop Out
The falling away of a body of sand when the mold is jarred or lifted.

Dropping the Bottom
Removal of the supporting props under the cupola bottom doors to permit emptying of the remaining contents. See Cupola.

Dross
Metal oxides and other scum on the surface of molten metal or in a metal or alloy (mostly a non-ferrous term).

Drum Ladle
A cylindrical refractory-lined ladle that is completely enclosed. A removable cover at the pouring spout permits addition of molten metal.

Drum, Magnetic
An electrically energized pulley or drum used for removing magnetic materials from sand, nonferrous borings and turnings, etc.

Dry Analysis
A term applied to spectrographic analysis.

Dry And Baked Compression Test
An AFS test to determine the maximum compressive stress that a baked sand mixture is capable of developing.

Dry Pan
A grinding machine of heavy rollers or millers testing on a bed. Screens or slits allow fine material to pass through.

Dry Permeability
Property of a molded mass of sand dried at 221°F to 230°F and cooled to room temperature, to permit passage of gases through it.

Dry Sand
Sand mixture that is baked to produce strong molds that are moisture free.

Dry Sand Casting
The process in which the sand molds are dried at above 212°F (100°C) before using.

Dry Sand Core
See Core.

Dry Sand Mold
A mold from which the moisture has been removed by heating.

Dry Strength, or Dry Bond Strength
The maximum compressive, shear, tensile, or transverse strength of a sand mixture which has been dried at 220°F to 230°F (105°C to 110°C) and cooled to room temperature.

Dryer, Core
See Core Driers.

Dryer, Dielectric
See Dielectric Oven.

Dry-Sand Mold
A mold made of prepared molding sand dried thoroughly before being filled with metal. See Mold, Molding Sand.

Dual Metal Centrifugal Casting
Centrifugal castings produced by pouring a different metal into the rotating mold after the first metal poured.

Ductile Iron
A type of iron in which the graphite content takes spherical rather than flake form. Ductile iron is produced by adding magnesium. The spherical form of the graphite provides greater tensile strengths and flexibility than other types of iron. An iron/graphite composite in which the graphite exists in spheres or nodules, allowing the material to deform rather than fracture when placed under mechanical stress. Also called Nodular Iron. Iron in which carbon is in the form of spherical nodules. See Nodular Iron.

Ductility
The property permitting permanent deformation by stress in tension with out rupture.

Duplexing
Term usually used in reference to melting metals or alloys in one type of furnace and transferring to another for holding, refining, etc. Common in the malleable field, where charges are melted in a cupola and transferred to air or electric furnaces for slight reduction of carbon and an increase in temperature.

Dust
Small solid particles created by the breaking up of larger particles by a process.

Dye Penetrant
Penetrant is used to crack detection, which has a dye added to make it more readily visible under normal or black-lighting conditions. In the case of normal lighting, the dye is usually red and nonfluorescent. With black lighting, the dye is fluorescent and yellow-green in color.

Eddy Current Testing
The detection of discontinuities by observation of the interaction between electromagnetic fields and metals.

Ejector Marks
Marks left on die castings by the ejector pins, which may be raised or depressed from the surface of the casting. See Die Casting, Ejector Pins.

Ejector Pins
Movable pins in pattern dies which help remove patterns from the die.

Ejector Plate
Movable plate beneath a shell molding pattern containing the pins for lifting or ejecting the hardened, resin-bonded shell mold from the pattern. See Shell Molding.

Elastic Limit
Maximum stress that a material will withstand without permanent deformation. See Yield Strength.

Elasticity
The property of recovering original shape and dimensions upon removal of a deforming force.

Electric Arc Furnace
A crucible furnace that uses an electric arc, similar to an electric arc welding operation, to melt metal. See Crucible Furnace.

Electrical Precipitator
In air pollution control, the use of electrodes in stack emissions emitting high voltage; particles 0.1 micron and smaller can be attached and collected at discharge electrode.

Electrochemical Corrosion (Contact Corrosion, Electrolytic Corrosion, Galvanic Corrosion)
Localized corrosion from exposure of an assembly of dissimilar metals in contact or coupled with one another, i.e., electrochemical action.

Electrode
Compressed graphite or carbon cylinder or rod used to conduct electric current in electric arc furnaces, arc lamps, carbon arc welding, etc.

Electron Microprobe Analyzer
An instrument for selective analysis of a microscopic area, in which an electron beam bombards the point of interest in Vacuo at a given energy level. Intensity of backscatter is measured to interpret which chemical elements are present, and by scanning a large area the microprobe can analyze chemical composition and indicate the distribution of an element.

Elongation
A measure of a material's ductility. Given in a percent, it indicates the amount a material will deform before permanent deformation. The higher the number, the more ductile. See Ductility.

Embrittlement
Loss of ductility of a metal due to chemical or physical change. See Acid Embrittlement, Ductility, Hydrogen Embrittlement.

Endothermic Reaction
The reaction which occurs with absorption of heat. See Exothermic Reaction.

End-Quench Hardenability Test
A standardized method for comparing the hardenability of different steels.

Engineering Strain(e)
The average linear strain, obtained by dividing the elongation of the length of the specimen by the original gage length.

Engineering Stress(es)
The load divided by the original area.

EPC (Expendable Pattern Casting)
See Lost Foam Process.

Equilibrium
Dynamic condition of balance between atomic movements where the resultant is zero, a stable condition and the condition appears to be one of rest rather than change.

Ergonomics
The science which deals with the interaction between people, their work place and environment. It also considers the physiology of workers in the design of tools, equipment, and the work methods needed.

Erosion
Abrasion of metal or other material by liquid or gas, usually accelerated by pressure of solid particles of matter in suspension, and sometimes by corrosion.

Erosion Scab
Casting defect occurring where the metal has been agitated, boiled, or has partially eroded away the sand, leaving a solid mass of sand and metal at that particular spot.

Etchant
A solution for chemical etching the polished surface of a metal specimen to reveal macro- or micro-structures.

Ethyl Silicate
Light brown liquid consisting predominantly of tetraethyl silicate with some polysilicates which can be hydrolized with water to form alcohol and silicic acid. Used as a bonding agent in investment molding. See Investment Casting.

Eutectic
The alloy which has the lowest melting point possible for a given composition. See Alloy.

Eutectic Reaction
Reaction in which a liquid solution solidifies or transforms at constant temperature to form a solid mass made up of tow kinds of crystals.

Eutectoid
A solid solution of any series which cools without change to its temperature of final composition.

Evaporation Pattern Casting / Expendable Pattern Casting / EPC
See Lost Foam Process.

Exothermic
Formed by or characterized by heat reaction as in oxidation.

Exothermic Reaction
Chemical reactions involving the liberation, or production, of heat. See Endothermic Reaction.

Expansion Scabs
Rough thin layers of metal partially separated from the body of the casting by a thin layer of sand, and held in place by a thin vein of metal.

Expansion, Sand
Dimensional increase that sand undergoes when subjected to elevated temperature conditions.

Expendable Pattern
In investment molding, the wax or plastic pattern that is left in the mold and later melted and burned out. This also called a disposable pattern.

Extensometer
An instrument used in the testing of metals to measure small increments of deformation.

External Chills
Various materials of high heat capacity such as metals, graphite, etc., forming parts of the walls of the mold cavity to promote rapid heat extraction from molten metal. See Mold Cavity.

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