A process in which Quid molecules are taken up by a liquid
or solid and distributed throughout the body of that liquid or
solid. Compare with adsorption.
Cooling a plate with water immediately following the final
rolling operation. Generally the plate is water cooled from
about 1400o F to approximately 1100o F
Accelerated corrosion test
Method designed to approximate, in a short time, the
deteriorating effect under normal long-term service
Accordion Reed Steel
Hardened, tempered, polished and blued or yellow flat
steel with dressed edges. Carbon content about 1.00. Material
has to possess good flatness, uniform hardness and high
A highly sub-structure, non-equiaxed ferrite formed upon
continuous cooling by a mixed diffusion and shear mode of
transformation that begins at a temperature slightly higher
than the transformation temperature range for upper bainite.
It is distinguished from bainite in that it has a limited
amount of carbon available thus, there is only a small amount
of carbide present.
A chemical substance that yields hydrogen ions (H+) when
dissolved in water. Compare with base.
Brittleness resulting from pickling steel in acid;
hydrogen, formed by the interaction between iron and acid, is
partially absorbed by the metal, causing acid brittleness.
A form of hydrogen embrittlement that may be induced in some
metals by acid.
process of making steel, either Bessemer, open-hearth or
electric, in which the furnace is lined with a siliceous
refractory and for which low phosphorus pig iron is required
as this element is not removed.
Atmospheric precipitation with a pH below 3.6 to 5.7. Burning
of fossil fuels for heat and power is the major factor in the
generation of oxides of nitrogen and sulfur, which are
converted into nitric and sulfuric acids washed down in the
rain. See also atmospheric corrosion.
melted in a furnace with an acid bottom and lining and under a
slag containing an excess of an acid substance such as silica.
Resin polymerized from acrylic acid, methacrylic acid,
eaters of these acids, or acrylonitrile.
The changing of a passive surface of a metal to a chemically
active state. Contrast with passivation.
A state in which a metal tends to corrode; referring to
the negative direction of electrode potential (opposite of
passive or noble).
A metal ready to corrode, or being corroded
The potential of a corroding material.
A measure of the chemical potential of a substance, where
chemical potential is not equal to concentration, that allows
mathematical relations equivalent to those for ideal systems
to be used to correlate changes in an experimentally measured
quantity with changes in chemical potential.
The ion concentration corrected for deviations from ideal
behavior. Concentration multiplied by activity coefficient.
activity coefficient. A characteristic of a quantity
expressing the deviation of a solution from ideal
thermodynamic behavior; often used in connection with
Actual throat thickness
The perpendicular distance between two lines each parallel to
a line joining the outer toes one being tangent at the weld
face and the other being through the furthermost point of
A substance added to a solution for the purpose of altering or
controlling a process. Examples include wetting agents in acid
pickles, brighteners or antipitting agents in plating
solutions, and inhibitors.
A substance added in a small amount, usually to a fluid, for a
special purpose, such as to reduce friction, corrosion, etc.
The surface retention of solid, liquid, or gas molecules,
atoms, or ions by a solid or liquid. Compare with absorption.
(1) Exposing to the action of air.
(2) Causing air to bubble
(3) Introducing air into a solution by spraying,
stirring, or a similar method.
(4) Supplying or infusing with
air, as in sand or soil.
An oxygen concentration cell; an electrolytic cell resulting
from differences in dissolved oxygen at two points. Also see
differential aeration cell..
The term as applied to soft or low carbon steels, relates to slow, gradual changes that take place in properties of steels after the final treatment. These changes, which bring about a condition of increased hardness, elastic limit, and tensile strength with a consequent loss in ductility, occur during the period in which the steel is at normal temperatures.
particles of limestone (flux) and iron ore are difficult to
handle and transport because of dusting and decomposition, so
the powdery material usually is processed into larger pieces.
The raw material's properties determine the technique that is
used by mills.
Baked particles that stick together in roughly
one-inch chunks. Normally used for iron ore dust collected
from the blast furnaces.
Iron ore or limestone particles are rolled into
little balls in a balling drum and hardened by heat.
Small lumps are formed by pressing material
together. Hot Iron Briquetting (HBI) is a concentrated iron
ore substitute for scrap for use in electric furnaces.
Spontaneous change in the physical properties of some metals, which occurs on standing, at atmospheric temperatures after final cold working or after a final heat treatment. Frequently synonymous with the term “ Age-Hardening.”
Thermal cutting using an arc for melting the metal and a
stream of air to remove the molten metal to enable a cut to be
Cooling of the heated metal, intermediate in rapidity between slow furnace cooling and quenching, in which the metal is permitted to stand in the open air.
A steel containing sufficient carbon and other alloying
elements to harden fully during cooling in air or other
gaseous mediums from a temperature above its transformation
range. Such steels attain their martensitic structure without
going through the quenching process. Additions of chromium,
nickel, molybdenum and manganese are effective toward this
end. The term should be restricted to steels that are capable
of being hardened by cooling in air in fairly large sections,
about 2 in. or more in diameter.
AISI (American Iron and Steel Institute)
An association of North American
companies that mine iron ore and produce steel products. There
are 50 member companies and more than 100 associate members,
which include customers that distribute, process, or consume
steel. The AISI has reorganized into a North American steel
trade association, representing the interests of Canada,
Mexico, and the United States. Common and alloy steels have
been numbered in a system essentially the same as the SAE. The
AISI system is more elaborate than the SAE in that all numbers
are preceded by letters: A represents basic open-hearth alloy
steel, B acid Bessemer carbon steel, C basic open-hearth
carbon steel, CB either acid Bessemer Or basic open-hearth
carbon steel, E electric furnace alloy
sheet produced by bonding either corrosion-resistant aluminum
alloy or aluminium of high purity to base metal of
structurally stronger aluminium alloy. The coatings are anodic
to the core so they protect exposed areas of the core
electrolytically during exposure to corrosive environment.
A metal in group lA of the periodic system - namely, lithium,
sodium, potassium, rubidium, cesium, and francium. They form
strongly alkaline hydroxides, hence the name.
(1) Having properties of an alkali.
(2) Having a pH greater
A material blended from alkali hydroxides and such alkaline
salts as borates, carbonates, phosphates, or silicates. The
cleaning action may be enhanced by the addition of
surface-active agents and special solvents.
Resin used in coatings. Reaction products of polyhydric
alcohols and polybasic acids
(1) A chemical process in which an alkyl radical is introduced
into an organic compound by substitution or addition.
refinery process for chemically combining isoparaffin with
(1) Pronounced wide cracking over the entire surface of a
coating having the appearance of alligator hide.
longitudinal splitting of flat slabs in a plane parallel to
the rolled surface. Also called fish-mouthing.
Metal prepared by adding other metals or non-metals to a basic metal to secure desirable properties.
Any metallic element added during the
making of steel for the purpose of increasing corrosion
resistance, hardness, or strength. The metals used most
commonly as alloying elements in stainless steel include
chromium, nickel, and molybdenum.
The codeposition of two or more metallic elements.
iron-based mixture is considered to be an alloy steel when
manganese is greater than 1.65%, silicon over 0.5%, copper
above 0.6%, or other minimum quantities of alloying elements
such as chromium, nickel, molybdenum, or tungsten are present.
An enormous variety of distinct properties can be created for
the steel by substituting these elements in the recipe.
Addition of such alloying elements is usually for the purpose
of increased hardness, strength or chemical
addition to the producer's selling price included in order to
offset raw material cost increases caused by higher alloy
A copper-zinc alloy containing up to 38% of zinc. Used mainly for cold working.
A copper-tin alloy consisting of the alpha solid solution of tin in copper. Commercial forms contain 4 or 5% of tin. This alloy is used in coinage, springs, turbine, blades, etc.
polymorphic form of iron, stable below 1670 (degrees) F. has a
body centered cubic lattice, and is magnetic up to 1410
A corrosion test in which the specimens are intermittently
exposed to a liquid medium at definite time intervals.
A gas welding technique in which the flame rightward welding
Forming of an aluminum or aluminum alloy coating on a metal by
hot dipping, hot spraying, or diffusion
Chemical symbol Al, Element No. 13 of the periodic system;
Atomic weight 26.97; silvery white metal of valence 3; melting
point 1220 (degrees) F; boiling point approximately 4118
(degrees) F.; ductile and malleable; stable against normal
atmospheric corrosion, but attacked by both acids and alkalis.
Aluminium is used extensively in articles requiring lightness,
corrosion resistance, electrical conductivity, etc. Its
principal functions as an alloy in steel making;
(2) Restricts grain growth (by forming
dispersed oxides or nitrides)
(3) Alloying element in
Aluminum Killed Steel
A steel where aluminum has been used as a deoxidizing
All-weld test piece
A block of metal consisting of one or more beads or runs fused
together for test purposes. It may or may not include portions
of parent metal.
All-weld test specimen
A test specimen that is composed wholly of weld metal over the
portion to be tested.
An alloy of mercury with one or more other metals
An instrument for measuring the magnitude of electric current
A rigid material whose structure lacks crystalline
periodicity; that is, the pattern of its constituent atoms or
molecules does not repeat periodically in three dimensions.
See also metallic glass..
A term applied to oxides and hydroxides which can act basic
toward strong acids and acidic toward strong alkalis.
Substances which can dissociate electrolytically to produce
hydrogen or hydroxyl ions according to conditions.
In the absence of air or unreacted or free oxygen.
A zinc-iron phosphate coating for iron and steel.
An ion or radical which is attracted to the anode because of
the negative charge. See also cation and ion
and holding at a suitable temperature and then cooling at a
suitable rate, for such purposes as reducing hardness,
improving machinability, facilitating cold working, producing
a desired microstructure, or obtaining desired mechanical,
physical, or other properties. When applicable, the following
more specific terms should be used: black annealing, blue
annealing, box annealing, bright annealing, flame annealing,
graphitizing, intermediate annealing, isothermal annealing,
malleablizing, process annealing, quench annealing,
re-crystallization annealing, and spherodizing. When applied
to ferrous alloys, the term annealing, without qualification,
implies full annealing. When applied to nonferrous alloys, the
term annealing implies a heat treatment designed to soften an
age-hardened alloy by causing a nearly complete precipitation
of the second phase in relatively coarse form. Any process of
annealing will usually reduce stresses, but if the treatment
is applied for the sole purpose of such relief, it should be
designated stress relieving.
A heat or thermal treatment process by which a previously
cold-rolled steel coil is made more suitable for forming and
bending. The steel sheet is heated to a designated temperature
for a sufficient amount of time and then cooled.
- WHY The bonds between the grains of the metal are
stretched when a coil is cold rolled, leaving the steel
brittle and breakable. Annealing "recrystallizes" the grain
structure of steel by allowing for new bonds to be formed at
the high temperature.
- HOW There are two ways to anneal cold-rolled steel
coils: batch and continuous.
(1) BATCH (BOX). Three to four coils are stacked on top
of each other, and a cover is placed on top. For up to three
days, the steel is heated in a non-oxygen atmosphere (so it
will not rust) and slowly cooled.
Normally part of a coating line, the
steel is uncoiled and run through a series of vertical loops
within a heater: The temperature and cooling rates are
controlled to obtain the desired mechanical properties for the
The electrode at which oxidation or corrosion of some
component occurs (opposite of cathode). Electrons flow away
from the anode in the external circuit.
The dissolution of a metal acting as an anode.
Anode corrosion efficiency
Ratio of actual to theoretical corrosion based on the total
current flow calculated by Faraday's law from the quantity of
electricity that has passed.
The effect produced by polarization of the anode in
electrolysis. It is characterized by a sudden increase in
voltage and a corresponding decrease in amperage due to the
anode becoming virtually separated from the electrolyte by a
Current efficiency of the anode.
- (1) The portion of solution in immediate contact with
the anode, especially if the concentration gradient is
- (2) The outer layer of the anode itself.
Electrolytic cleaning in which the work is the anode. Also
called reverse-current cleaning.
A film on a metal surface resulting from an electrolytic
treatment at the anode.
A chemical substance or combination of substances that prevent
or reduce the rate of the anodic or oxidation reaction by a
physical, physico-chemical or chemical action
The change in the initial anode potential resulting from
current flow effects at or near the anode surface. Potential
becomes mode noble (more positive) because of anodic
An appreciable reduction in corrosion by making a metal an
anode and maintaining this highly polarized condition with
very little current flow.
A technique to reduce corrosion of a metal surface under some
conditions by passing sufficient to it to cause its electrode
potential to enter and remain in the passive region; imposing
an external electrical potential to protect a metal from
corrosive attack. (Applicable only to metals that show
active-passive behavior.) Contrast with cathodic protection.
Electrode reaction equivalent to a transfer of positive charge
from the electronic to the ionic conductor. An anodic reaction
is an oxidation process. An example common in corrosion is: Me
~ Me n+ + ne .
Anodizing (Aluminum Anodic Oxide Coating)
A process of coating aluminum by anodic treatment
resulting in a thin film of aluminum oxide of extreme
hardness. A wide variety of dye colored coatings are possible
by impregnation in process.
The electrolyte adjacent to the anode in an electrolytic cell.
Intended to prevent fouling of under-water structures, such as
the bottoms of ships; refers to the prevention of marine
organism's attachment or growth on a submerged metal surface,
generally through chemical toxicity caused by the composition
of the metal or coating layer.
An addition agent for electroplating solutions to prevent the
formation of pits or large pores in the electrodeposit.
Pertaining to water; an aqueous solution is made by using
water as a solvent.
A lengthening or deflection of a DC welding arc caused by
the interaction of magnetic fields set up in the work and arc
The fan-shaped flame associated with the atomic-hydrogen arc.
The voltage between electrodes or between an electrode and the
work, measured at a point as near as practical to the work.
Argon-Oxygen Decarburization (AOD)
of welding processes wherein the metal or metals being joined
are coalesced by heating with an arc, with or without the
application of pressure and with or without the use of filler
A process for further refinement of
stainless steel through reduction of carbon content.
The amount of carbon in stainless steel must be
lower than that in carbon steel or lower alloy steel (i.e.,
steel with alloying element content below 5%). While electric
arc furnaces (EAF) are the conventional means of melting and
refining stainless steel, AOD is an economical supplement, as
operating time is shorter and temperatures are lower than in
EAF steelmaking. Additionally, using AOD for refining
stainless steel increases the availability of the EAF for
Molten, unrefined steel is transferred from the EAF
into a separate vessel. A mixture of argon and oxygen is blown
from the bottom of the vessel through the melted steel.
Cleaning agents are added to the vessel along with these gases
to eliminate impurities, while the oxygen combines with carbon
in the unrefined steel to reduce the carbon level. The
presence of argon enhances the affinity of carbon for oxygen
and thus facilitates the removal of carbon.
An aging treatment above room temperature. (See Precipitation Heat Treatment and compare with natural aging).
for American Society For Testing Material. An organization for
issuing standard specifications on materials, including metals
The gradual degradation or alteration of a material by contact
with substances present in the atmosphere, such as oxygen.
carbon dioxide, water vapor, and sulfur and chlorine
A natural reduction in work force as a result of resignations,
retirements, or death.
Arc welding in which molecular hydrogen, passing through an
arc between two tungsten or other suitable electrodes, is
changed to its atomic form and then re-combines to supply the
heat for welding
Most unionized companies cannot unilaterally reduce
their employment levels to cut costs, so management must rely
on attrition to provide openings that they, in turn, do not
fill. Because the median ages of work forces at the integrated
mills may be more than 50, an increasing number of retirements
may provide these companies with added flexibility to improve
Quenching a ferrous alloy from a temperature above the
transformation range, in a medium having a rate of heat
abstraction high enough to prevent the formation of
high-temperature transformation products, and then holding the
alloy, until transformation is complete, at a temperature
below that of pearlite formation and above that of martensite
Phase in certain steels, characterized as a solid solution, usually off carbon or iron carbide, in the gamma form of iron. Such steels are known as “austenitic”. Austenite is stable only above 1333°F. in a plain carbon steel, but the presence of certain alloying elements, such as nickel and manganese, stabilizes the austenitic form, even at normal temperatures.
largest category of stainless steel, accounting for about 70%
of all production. The austenitic class offers the most
resistance to corrosion in the stainless group, owing to its
substantial nickel content and higher levels of chromium.
Austenitic stainless steels are hardened and strengthened
through cold working (changing the structure and shape of
steel by applying stress at low temperature) instead of by
heat treatment. Ductility (ability to change shape without
fracture) is exceptional for the austenitic stainless steels.
Excellent weldability and superior performance in very
low-temperature services are additional features of this
class. Applications include cooking utensils, food processing
equipment, exterior architecture, equipment for the chemical
industry, truck trailers, and kitchen sinks. The two most
common grades are type 304 (the most widely specified
stainless steel, providing corrosion resistance in numerous
standard services) and type 316 (similar to 304 with
molybdenum added, to increase opposition to various forms of
Steel which, because of the presence of alloying elements, such as manganese, nickel, chromium, etc., shows stability of Austenite at normal temperatures.
Forming austenite by heating a ferrous alloy into the
transformation range (partial austenitizing) or above the
transformation range (complete austenitizing). When used
without qualification, the term implies complete austenitizing.
Auto Stamping Plant
facility that presses a steel blank into the desired form of a
car door or hood, for example, with a powerful die (pattern).
The steel used must be ductile (malleable) enough to bend into
shape without breaking.
Automatic Gauge Control
Using hydraulic roll force systems, steelmakers
have the ability to control precisely their steel sheet's
gauge (thickness) while it is traveling at more than 50 miles
per hour through the cold mill. Using feedback or feed-forward
systems, a computer's gap sensor adjusts the distance between
the reduction rolls of the mill 50-60 times per second. These
adjustments prevent the processing of any off-gauge steel
radiograph recorded photographically by radiation
spontaneously emitted by radioisotopes that are produced in,
or added to, the material. This technique identifies the
locations of the radioisotopes.
In electroplating, a supplementary anode positioned so as to
raise the current density on a certain area of the cathode and
thus obtain better distribution of plating.
An electrode commonly used in polarization studies to pass
current to or from a test electrode, usually made of
non- corroding material.