All terms related to Foundry and Metallurgy
Alloy Steel
Steel containing significant quantities of alloying elements other than carbon and the commonly accepted amounts of manganese, silicon, sulfur, and phosphorus.
As Cast
Referring to metal which has not received finishing (beyond gate removal or sandblasting) or treatment of any kind including heat treatment after casting. Similarly, as drawn, as forged and as rolled.
Austenite Steel
Any steel containing sufficient alloy to produce a stable austenitic (gamma iron) crystalline structure at ambient temperatures.
Casting
Metal object cast to require shape by pouring liquid metal into a mould.
Copper
For foundry applications, copper is meant to include all alloys containing 98% or more copper. Used for conductivity castings. Melting point 1083°C (1981.4°F).
Core
A performed sand aggregate inserted in a mold to shape the interior or that part of a casting which cannot be shaped by the pattern.
Cracking Strip
A fin of metal molded on the surface of a casting to prevent cracking.
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.
Die
A metal block used in forming materials by casting, molding, stamping, threading, or extruding.
Die Assembly
The parts of a die stamp or press that hold the die and locate it for the punches.
Die Casting
A rapid, water-cooled permanent mold casting process limited to nonferrous metals. There are three types: the plunger-type operated hydraulically, mechanically or by compressed air with or without a gooseneck; the direct-air injection which forces metal from a goose-neck into the die, and the Cold-Chamber Machine. All force the metal into the die with a pressure greater than that of gravity flow.
Dirty Casting
A casting containing an excessive amount of nonmetallic inclusions in the body of the metal.
Disturbed Metal
The cold worked metal formed on a polished surface during the processes of grinding and polishing.
Dry Sand Casting
The process in which the sand molds are dried at above 100°C (212°F) before using.
Dust
Small solid particles created by the breaking up of larger particles.
Fatigue Crack or Failure
A fracture starting from a nucleus where there is an abnormal concentration of cyclic stress. The fracture surface is smooth and frequently shows concentric (sea shell) markings with a nucleus as a center.
Feeding
The process of supplying molten metal to compensate for volume shrinkage while the casting is solidifying.
Heat Treatment
A combination of heating and cooling operations and applied to a metal or alloy to produce desired properties and microstructures.
High-Alloy Steel
Ferrous alloy with more than 12 weight percent of noncarbon additions.
High Pressure Mold
A strong high-density mold, made by air, hydraulic, or other squeeze process.
HSLA
High Strength Low Alloy Steel. Steel with relatively high strength and impact properties. The carbon level is low and the alloying additions are significantly less than 5 weight percent.
Hypereutectoid Steel
A steel containing more than the eutectoid percentage of carbon (0.83 wt. %).
Impurity
An element unintentional allowed in a metal or alloy. Some impurities have little effect on properties; others will grossly damage the alloy.
Induction Hardening
A surface hardening process involving the localized use of pulsating magnetic currents to achieve heating above the austenite transformation temperature, Ac3, followed by quenching.
Induction Heating
Process of heating by electrical resistance and hysteresis losses induced by subjecting a metal to the varying magnetic field surrounding a coil carrying an alternating current.
Injection Molding
The injection of molten metal or other material under pressure into molds.
Insert
A part usually formed from metal, which is placed in a mold and may become an integral part of the casting.
Internal Shrinkage
A void or network of voids within a casting caused by inadequate feeding of that section during solidification.
Jobbing Foundry
A foundry engaged in the manufacture of numerous types of castings.
Ladle
Metal receptacle frequently lined with refractories used for transporting and pouring molten metal. Types include hand bull, crane, bottom-pour, holding, teapot, shank, lip-pour.
Martensitic Stainless Steels
A corrosion-resistant ferrous alloy with a predominant martensitic phase.
Metallurgy
The science and technology of metals, a broad field that includes but is not limited to the study of internal structures and properties of metals and the effects on them of various processing methods.
Molybdenum
A metal used widely in alloying of other metals. It is used as hardening element for steel, and for diecasting dies. Melting point 2620°C (4748°F), atomic number 42.
Nickel
Element used for alloying iron and steel as well as nonferrous metals; melting point 1455°C (2651°F). Nickel is also a base metal for many casting alloys resistant to corrosion and high temperature oxidation.
Ni-Hard
Hard white cast iron containing 4% Ni and 2% Cr.
Nonferrous
A negative term, refers to alloy in which the predominate metal or solvent is not iron.
Normal Steel
Steel in which the pearlite is completely laminated.
Penetration, Metal
Condition where molten metal has penetrated into the sand, resulting in a mixture of metal and sand adhering to the casting.
Permanent Mold
A metal mold of two or more parts; not an ingot mold. It is used repeatedly for the production of many casting of the same form.
Pipe
A cavity formed by shrinkage of the metal during solidification, usually occurring in a riser having feeder metal for the casting.
Pouring
Transfer of molten metal from furnace to ladle, ladle to ladle, or ladle into molds.
Profile Tolerances
A system of locating and tolerancing developed to control the orientation of rough parts in machine fixtures. From locating points on the casting a "perfect profile" is established for all surfaces and features. A tolerance envelope surrounding that profile defines the limitations of an acceptable part.
Quench Crack
A crack resulting from thermal stress induced during rapid cooling or quenching, or from stresses induced by delayed transformations some time after the article has been fully quenched.
Quenching
Rapid cooling of hardening; normally achieved by immersion of the object to be hardened in water, oil, or solutions of salt or organic compounds in water.
Runout
A casting defect caused by incomplete filling of the mold due to molten metal draining or leaking out of some part of the mold cavity during pouring; escape of molten metal from a furnace, mold or melting crucible.
Sand
In metalcasting, a loose, granular material high in SiO2, resulting from the disintegration of rock. The name sand refers to the size of grain and not to mineral composition. Diameter of the individual grains can vary from approximately 6 to 270 mesh. Most foundry sands are made up principally of the mineral quartz (silica). Reason for this is that sand is plentiful, refractory, and cheap; miscellaneous sands include zircon, olivine, chromite, CaCO3, black sand (lava grains), titanium minerals and others.
Sand Casting
Metal castings produced in a green sand, dried sand or core sand mould.
Sand Control
Procedure whereby various properties of foundry sand, such as fineness, permeability, green strength, moisture content, etc., are adjusted to obtain castings free from blows, scabs, veins, and similar defects.
Scab
An expansion discontinuity defect on the surface of a casting which appears as a rough, slightly raised surface blemish, crusted over by a thin porous layer of metal under which is a honeycomb or cavity that usually contains a layer of sand.
Scaling (Scale)
Surface oxidation, partially adherent layers of corrosion products, left on metals by heating or casting in air or in other oxidizing atmospheres.
Scarfing
Cutting off surface projections such as gates and risers from casting by means of gas torch.
Scrap (Metal)
Metal to be remelted; includes scrapped machinery fabricated items such as rail or structural steel and rejected castings.
Seam
A surface defect on a casting related to but of lesser degree than a Cold Shut; a ridge on the surface of a casting caused by a crack in the mold face.
Shell Molding
A process for forming a mold from resin-bonded sand mixtures brought in contact with pre-heated (150-250°C / 300-500°F) metal patterns, resulting in a firm shell with a cavity corresponding to the outline of the pattern.
Shift
A casting defect caused by mismatch of cope and drag or of cores and mold.
Silica Sand
Sand with a minimum silica content of 95% used for forming casting molds.
Shewed Tolerances
Tolerances which are non-symmetrically distributed about the design parameter.
Skim Core (Skimmer)
A flat core or tile placed in a mold to skim a flowing stream of metal. Commonly used in pouring basins, it hold back slag and dirt while clean metal passes underneath to the downsprue.
Skim Gate
A gating arrangement which changes the direction of flow of molten metal and prevents the passage of slag and other undesirable materials into the mold cavity.
Skimming
Removing or hold back dirt or slag from the surface of the molten metal before or during pouring.
Skin
A thin surface layer different chemically or structurally from the main mass of a metal object.
Skin-Drying
Drying the surface of the mold by direct application of heat.
Slag Inclusion
Nonmetallic solids entrapped in solid metal.
Slag Trap
An enlargement, dam, or extrusion in the gating or runners system in a mold for the purpose of preventing molten slag particles from entering the mold cavity.
Slicking (Sleeking)
Smoothing the surface of molds.
Slurry
A term loosely applied to any clay-like dispersion. It may be use to wash ladles or other refractory linings to impart a smooth surface; as a bonding addition to molding sand; as a thin loam over specially made molds or as a mixture to fine joints or cracks of a core, etc.
Smelting
A metallurgical thermal process in which a metal is separated in fused form from nonmetallic materials or other undesired metals with which it is associated.
Stainless Steel
A wide range of steels containing chromium or chromium and nickel, exhibiting high resistance to corrosion.
Steel
An alloy of iron and carbon that may contain other elements and in which the carbon content does not exceed about 1.7%; it must be malleable at some temperature while in the as-cast state.
Sticker
A lump on the surface of a casting caused by a portion of the mold face sticking to the pattern. Also, a forming tool used in molding.
Stress-Corrosion Cracking
Spontaneous failure of metals by cracking under combined conditions of corrosion and stress, either residual or applied.
Stress, Relieving
A heat treatment to reduce residual stresses followed by sufficiently slow cooling to minimize development of new residual stresses.
Stress, Residual
Those stresses setup up in a metal as a result of nonuniform plastic deformation or the unequal cooling of a casting.
Strike-Off
Operation of removing excess sand from top or core box or flask.
Stripping
Removing the pattern from the mold or core box from core.
Structurals
Steel product group that includes I-beams, H-beams, wide-flange beams and sheet piling. These products are used in the construction of multi-story buildings, industrial buildings, bridge trusses, vertical highway supports, and riverbank reinforcement.
Sulfur
A nonmetallic element, melting point 444°C (831.2°F) occurring as an undesirable tramp (trace) element in most ferrous alloys.
Surface Hardening
Conferring a superficial hardness to a steel while maintaining a relatively soft core.
Surfacing
Depositing a filer metal on a metal surface by any method to obtain certain desired properties or dimensions.
Swell
A casting defect consisting of an increase in metal section due to the displacement of sand by metal pressure.
Synthetic Molding Sand
Any sand compounded from selected individual materials which, when mixed together, produce a mixture of the proper physical and mechanical properties from which to make foundry molds.
System Sand
Foundry sand used in making molds and which eventually becomes the bulk of the sand used in the mechanical system or mechanized unit.
Tool Steel
Any high-carbon or alloy steel used to make a cutting tool for machining metals and for metal-casting dies.
Upgrading
In castings, the removal and repair of discontinuities to raise the quality level of the casting beyond that which can be economically achieved by good foundry practice.
Vacuum Casting
A casting in which metal is melted and poured under very low atmospheric pressure; a form of permanent mold casting where the mold is inserted into liquid metal, vacuum is applied, and metal drawn up into the cavity.
Veins
A discontinuity on the surface of a casting appearing as a raised, narrow, linear ridge that forms upon cracking of the sand mold or core due to expansion of the sand during filling of the mold with molten metal.
Warpage
Deformation other than contraction that develops in a casting between solidification and room temperature; also, distortion occurring during annealing, stress relieving, and high-temperature service.
Wash
A casting defect resulting from erosion of sand by metal flowing over the mold or corded surfaces. They appear as rough spots and excess metal on the casting surface. Also call cuts.
Washburn Core
A thin core which constricts the riser at the point of attachment to the casting. The thin core heats quickly and promotes feeding of the casting. Riser removal cost is minimized.
Welding
A process used to join metals by the application of heat. Fusion welding, which includes gas, arc, and resistance welding, requires that the parent metals be melted.
Welding, Autogenous
Method of uniting two pieces of metal by melting their edges together without solder or any added welding metal, as by the thermite process that employs a medium of finely divided aluminum powder and oxide or iron by which a temperature of some 2982.2°C (5400°F) is obtained.
Welding Electrode
A metal or alloy in rod or wire forms used in electric arc welding to maintain the arc and at the same time supply molten metal or alloy at the point where the weld is to be accomplished.
Welding Flash
Skin exposed too long to the ultraviolet rays of welding or melting arcs will burn as in a sunburn. Though temporary blindness can result, it is not permanent, as is popularly believed.
Welding Stress
That stress resulting from localized heating and cooling of metal during welding.