The most frequently used terms and definitions,
related to iron castings, according to ASTM A 644 - 85 are
listed bellow.

Austenitize - to convert the matrix of a ferrous alloy to
austenite by heating above the transformation temperature.
Batch - the component raw materials properly weighed,
proportioned, and mixed for delivery to a processing unit. Also,
the product output from a processing unit in which there is
essentially no product output until all component materials are
charged and processed.
Carbide, primary - carbide precipitated in cast iron
during solidification.
Cast iron - a generic term for a series of alloys
primarily of iron, carbon, and silicon in which the carbon I in
excess of the amount which can be retained in solid solution in
austenite at the eutectic temperature.
Cementite - a very hard and brittle compound of iron and
carbon corresponding to the empirical formula Fe3C, commonly
known as iron carbide.
Cementite, primary - cementite precipitated in cast iron
during solidification. Also known as primary carbide.
Chilled iron - a cast iron that would normally solidify
as a gray cast iron which is purposely caused to solidify as
white cast iron locally or entirely by accelerated cooling
caused by contact with a metal surface, that is, a chill.
Direct reduced iron - iron ores that have been reduced to
essentially metallic iron by heat and reducing agents, but
without melting, and processed into suitable shapes for use as a
charge material in a melting operation.
Dual metal - two metals of different composition that are
fusion bonded at all interfacial surfaces by casting metal of
one composition against metal of a second composition.
Ductile iron - a cast iron that has been treated in the
liquid state so as to cause substantially all of its graphitic
carbon to occur as spheroids or nodules in the as-cast
condition.
Ferritize - to increase the quantity of ferrite in the
matrix of a ferrous casting through an appropriate heat
treatment.
Ferritizing anneal - the process of producing a
predominantly ferritic matrix in cast iron through an
appropriate heat treatment.
Graphite, compacted - a graphite shape that is
intermediate between flake graphite and nodular graphite that
typically appears in a polished section as thick flakes with
blunt ends.
Graphite, flake - an irregularly shaped particle of
graphite, usually appearing in a polished section as curved
plates, such as found in gray cast irons.
Graphite, nodular - spheroidal shaped graphite typically
found in ductile irons and compact clusters of graphite
typically found in malleable irons.
Graphite, primary - graphite precipitated in cast iron
during solidification.
Graphite rosette - arrangement of graphite flakes in
which the flakes extend radially from centers of crystallization
in gray cast iron.
Graphite, spheroidal - spheroidal shaped graphite having
a polycrystalline radial structure, usually found in ductile
iron and to a controlled, limited extent in compacted graphite
iron.
Graphitize - to precipitate graphite in an iron-carbon
alloy.
Gray iron - cast iron that has a relatively large
proportion of the graphitic carbon present in the form of flake
graphite. The metal has a gray fracture.
Heat - the total molten metal output from a single
heating in a batch melting process or the total metal output
from essentially a single heating in a continuous melting
operation using basically constant charge and processing
conditions and targeted at a fixed metal chemistry at the
furnace spout. A heat can also be defined as a fixed time period
for a continuous melting operation provided that it is shorter
than the time period covered by the above definition.
Inoculating alloy - an alloy added to molten iron for the
principle purpose of nucleating a primary phase such as
graphite. Inoculating alloys are frequently used to avoid the
formation of primary carbide by enhancing the nucleation of
graphite.
Malleable, ferritic - a ferrous alloy that is cast as
white is converted by an appropriate heat treatment to a
microstructure of temper carbon embedded in a ferritic matrix
essentially free of pearlite and carbide.
Malleable iron - a cast iron of such composition that it
solidifies as white iron, which upon proper heat treatment is
converted to a metallic matrix with nodules of temper carbon.
Malleable, pearlitic - a ferrous alloy that is cast as
white iron but which is converted by an appropriate heat
treatment to a microstructure of temper carbon embedded in a
matrix containing a controlled quantity, form, and distribution
of pearlite or tempered martensite.
Malleableize - to convert white iron into malleable iron
through an appropriate graphitizing heat treatment.
Melt - the total molten metal produced in a single heat.
Merchant pig iron - pig iron produced for commercial sale
to foundries.
Mottled iron - a cast iron containing a mixed structure
of gray iron and white iron of variable proportions. The
fracture has a mottled appearance.
Nodular graphite - graphite in the form of nodules or
spheroids in iron castings.
Nodularity - the volumetric proportion of spheroidal or
nodular graphite to total graphite in a ductile iron or a
compacted graphite iron matrix.
Nodularity, degree of - the volumetric proportion of
spheroidal or nodular graphite to total graphite in a ductile
iron matrix.
Nodulizing alloy - an alloy added to molten iron for the
primary purpose of causing the formation of spheroidal graphite
during solidification.
Pig iron - the high carbon iron product obtained by the
reduction of iron ores, typically in a blast furnace or an
electric furnace, and cast into uniform shapes having physical
and chemical characteristics suitable for end as foundry melting
stock.
Sample - one or more portions of a liquid or solid
material taken in an unbiased manner from a batch, heat, lot or
process stream to be representative of the whole, for subsequent
testing to determine the chemical, physical, mechanical, or
other quality characteristics of the material, or combination
thereof.
Temper carbon - compact aggregates or nodules of graphite
found in malleable iron as a result of heat treatment.
Test bar - a bar-shaped coupon that is tested with or
without subsequent preparation for the determination of physical
or mechanical properties.
Test coupon - specially designed casting, or portion
thereof, that is used to provide a representative sample of the
iron from which it was cast.
Test lug - a sample produced as an appendage on a
casting, that may be removed and tested to qualify the casting
or the iron which it was produced.
Test specimen - a test object, suitably prepared from a
sample, for evaluation of the chemical, physical, mechanical, or
metallurgical quality of the sample.
Treated iron - molten cast iron to which all basic alloys
and nodulizing alloys have been added but not necessarily all
inoculating alloy additions.
White iron - cast iron in which substantially all of the
carbon is in solution and in the combined form. The metal has a
white fracture.
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