The Glossary of Foundry and Casting
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.
Immersion cleaning aided by ultrasonic waves which cause
A nondestructive method of testing metal for flaws based on the fact
that ultrasonic waves are reflected and refracted at the boundaries
of a solid medium. Ultrasonic testing is used to detect flaws in
Part of a mold or die requiring a drawback. See Drawback.
A wild steel insufficiently deoxidized so that it evolves gas and
blowholes during solidification. See Killed Steel.
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. See Casting, Foundry.
Upper Yield Point (Also Yield Point)
Denoted in yield point phenomenon as a distinct break from the
elastic region accompanied by a drop in load, yet prior to plastic
deformation in the stress-strain curve in a low-carbon steel.
An addition to any flask part to increase height or depth.
Urea Formaldehyde Resin
A thermosetting product of condensation from urea or thio-urea and
formaldehyde, soluble in water and used as a sand binder in core and
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. See Cavity, Mold, Mold Casting.
The use of a vacuum technique to remove dissolved gases such as
hydrogen, oxygen, and nitrogen from molten alloys.
Melting, usually by induction heating, in a closed container which
is subjected to a vacuum.
Melting in a vacuum, usually by electrical induction, to remove
gaseous contaminants from the metal.
In manufacturing, an analysis to determine the most economical
method of manufacturing, taking into account the cost and the
process capability of alternate manufacturing systems under
consideration, their degree of variation, the benefits of the
resultant product, and desired quality and production quantity and
A white, hard, metallic element, mp 1800°C (3272°F), used as an
alloy in iron and steel; a powerful carbide stabilizer and
Oils extracted from plants, used as drying oils in oil core
manufacture. Linseed oil is an example.
Surface defect on castings appearing as veins or wrinkles, which
results from cracks in the sand due to elevated temperature
conditions and occurs mostly in cores. See Casting, Cores, Defect.
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. See Defect.
Small opening or passage through which gases can escape during the
pouring of a mold. It is alco called a vent hole.
A piece of wire or bar to form the vents in the sand.
Wax in rod shape placed in the core during manufacture. In the oven
the wax is melted out, leaving a vent or passage.
Perforation with a vent wire of the sand over and around a mold
cavity to assist in the escape of the gases.
Vertical Axis Casting Machine
A centrifugal casting machine in which the axis of rotation of the
mold is vertical.
A mechanical device, operated by compressed air or electricity, used
to loosen a pattern from a mold by jarring or vibration as it is
withdrawn from the sand.
The diamon pyramid used in Vickers Hardness Testing. See Vickers
Vickers Diamond Pyramid Hardness Tester
Patented indentation hardness machine. See Hardness.
Vickers Hardness Test
A method of determining the hardness of steel using a diamond
pyramid that is pressed into the polished surface of the specimen
and the diagonals of the impression are measured with a microscope
fitted with a micrometer eye piece. The rate of application and
duration are automatically controlled and the load can be varied.
See Vickers Diamond.
Virgin Metal (Primary Metal)
Metal extracted directly from the ore; not previously used.
The resistance of fluid substance to flowing, quantitatively
characteristic for an individual substance at a given temperature
and under other definite external conditions.
A shrinkage cavity produced in casting during solidification. See
Casting, Cavity, Shrinkage, Solidification.
A casting technique.
Warm Box Process
Coremaking method in which the corebox is warm when the core sand is
introduced. The warmth of the corebox initiates curing but does not
complete it. Cores finish curing outside the corebox (sometimes in a
separate dryer), allowing for faster core production cycles than
with the Hot Box process. Cores created using this process must be
solid- they cannot be shell cores. See Cores, Core Box, Hot Box
Deformation other than contraction that develops in a casting
between solidification and room temperature; also, distortion
occurring during annealing, stress relieving, and high-temperature
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. See Cut,
Thin core which constricts the riser at the point of attachment to
(Neck-Down Core) the casting. See Casting, Cores, Risers.
Refractory coating applied to molds and cores to provide protection
against penetration from molten metal. See Cores, Molds.
Sodium silicate (an inorganic binder system), a viscous liquid which
when mixed with powered fireclay forms a refractory cement.
To subject a casting to water pressure in such a manner that any
porous areas will show leakage.
Class of substances of plant, animal, or mineral origin, insoluble
in water, partly soluble in alcohol, either, etc., and miscible in
all proportions with oils and fats. They consist of esters, free
fatty acids, free alcohols, and higher hydrocarbons. Common waxes
are beeswax, bayberry, paraffin wax, ozokerite, ceresin, and
carnauba. Their mixtures are formed into rods and sheets and used
for forming vents in cores and molds, repairing patterns, etc.
A precise duplicate, allowing for shrinkage, of the casting and
required gates, usually formed by pouring or injecting molten wax
into a die or mold. Wax molded around the parts to be welded by a
termite welding process.
Sand lacking in the proper amount of bond. See Bond.
The undesired deterioration of a component by the removal of
material from its surface.
The built-up portion of a fusion weld, formed either from the filler
metal or the melting of the parent metal.
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.
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.
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.
Electric-arc welding in which the molten weld metal is protected
from the atmosphere. An inert gaseous atmosphere or fluxcoated
electrode may be employed.
That stress resulting from localized heating and cooling of metal
Welding accomplished by using an electric arc that can be formed
between a metal or carbon electrode and the metal being welded;
between two separate electrodes, as in atomic hydrogen welding or
between the two separate pieces being welded, as in flash welding.
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.
Lower portion of a cupola, between the sand bottom and the slaghole,
which forms a reservoir for the molten metal. See Cupola.
Wet Scrubber (Gas Washer)
In air pollution control, a liquid (usually water) spray device for
collecting pollutants in escaping foundry gases.
Surface-active agent which by reducing surface tension of the
wetting liquid causes a material to be wetted more easily.
Gating system in which the metal enters a circular reservoir at a
tangent, and so whirls around, leaving dirt and slag behind before
passing into the mold cavity.
Small openings from isolated mold cavities to allow gases to escape
easily. See Vent.
White Cast Iron
Cast iron in which substantially all the carbon is present in the
form of iron carbide, and which has a white fracture.
Plate-like structure seen in grains of steel in the course of
transformation of a solid solution.
Steel which has not been completely deoxidized and reacts violently
after casting due to liberation of gases of cooling.
Finely ground wood, usually hardwood, low in resin.
A form of radiant energy with extremely short wave length which has
the ability to penetrate materials that absorb or reflect ordinary
light. X-Rays provide a form of Non-Destructive testing.
Comparison of finished casting weight verses total weight of metal
poured in a mold. A value expressed as a percentage indicating the
relationship of the weight of a casting to the total composite of
the casting and its gating system.
The ratio of yield strength to ultimate tensile strength.
A measure of the amount of mechanical stress a material can
withstand before it permanently deforms.
Natural zirconium silicate, ZrSiO4 containing 67.23% zirconium
oxide, ZrO4, and 32.77% silica, SiO2, is used as a molding medium in
ZrO2 an acid refractory up to 2,500°C (4,532°F) having good thermal
shock resistance and low electrical resistively.
Silvery-white, metallic element, mp 1,860°C (3,380°F), a powerful
deoxidizer when added to molten steel.