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
A slender, needle-like (acicular) microstructure appearing
in spring steel strip characterized by toughness and greater
ductility than tempered Martensite. Bainite is a decomposition
product of Austenite (see Austenite) best developed at interrupted
holding temperatures below those forming fine pearlite and above
those giving Martensite.
Appearance of a metal, under a microscope or viewed by the
naked eye, on fractured or moothed surfaces, with or without
etching, showing parallel bands in the direction of rolling or
working.
A hardened tempered bright polished high carbon cold rolled
spring steel strip produced especially for use in the manufacture
of band saws for sawing wood, non ferrous metals, and plastics.
Usually carries some nickel and with a Rockwell value of approximately
C40/45.
Surface of metal, under the oxide-scale layer, resulting from
heating in an oxidizing environment. In the case of steel, such
bark always suffers from decarburization.
(See Tin Plate Base Box)
(See Open Hearth Process)
A steel making process wherein oxygen of the highest purity
is blown onto the surface of a bath of molten iron contained
in a basic lined and ladle shaped vessel. The melting cycle duration
is extremely short with quality comparable to Open Hearth Steel.
A steel making process either Bessemer, open hearth or electric,
in which the furnace is lined with a basic refractory. A slag,
rich in lime, being formed and phosphorous removed.
(See Basic Process)
Immersion in a liquid bath (such as molten lead or fused salts)
held at an assigned temperature. When a lead bath is used, the
process is known as lead annealing.
The only commercial ore of aluminum, corresponding essentially
to the formula Al2O3xH2O.
Raising a ridge on sheet metal.
Various tests used to determine the toughness and ductility
of flat rolled metal sheet, strip or plate, in which the material
is bent around its axis or around an outside radius. A complete
test might specify such a bend to be both with and against the
direction of grain. For testing, samples should be edge filed
to remove burrs and any edgewise cracks resulting from slitting
or shearing. If a vice is to be used then line the jaws with
some soft metal or brass, so as to permit a free flow of the
metal in the sample being tested.
An alloy of copper and 2-3% beryllium with optionally fractional
percentages of nickel or cobalt. Alloys of this series show remarkable
age-hardening properties and an ultimate hardness of about 400
Brinell (Rockwell C43). Because of such hardness and good electrical
conductivity, beryllium-copper is used in electrical switches,
springs, etc.
A steel making process in which air is blown through the molten
iron so that the impurities are thus removed by oxidation.
(See Bloom)
An alloy containing two elements, apart from minor impurities,
as brass containing the two elements copper and zinc.
A process of box annealing or pot annealing ferrous alloy sheet,
strip or wire after hot working and pickling. (See Box Annealing)
(Scaleless Blue.) A flat cold rolled usually .70/.80% medium
high carbon spring steel strip, blue-black in color, which has
been quenched in oil and drawn to desired hardness. While it
looks and acts much like blue tempered spring steel and carries
a Rockwell hardness of C44/47, it has not been polished and is
lower in carbon content. Used for less exacting requirements
than clock spring steel, such as snaps, lock springs, hold down
springs, trap springs, etc. It will take a more severe bend before
fracture than will clock spring, but it does not have the same
degree of spring-back.
A light weight or a thin uncoated steel sheet or strip so called
because of its dark oxide coloring prior to pickling. It is manufactured
by two different processes. (1) From sheet bar on single stand
sheet mills or sheer mills in tandem. This method is now almost
obsolete. (2) On modern, high speed continuous tandem cold reduction
mills from coiled hot rolled pickled wide strip into ribbon wound
coils to finished gage. Sizes range from 12” to 32” in
width, and in thicknesses from 55 lbs. to 275 lbs. base box weight.
It is used either as is for stampings, or may be enameled or
painted or tin or terne coated.
A vertical shaft type smelting furnace in which an air blast
is used, usually hot, for producing pig iron . The furnace is
continuous in operation using iron ore, coke, and limestone as
raw materials which are charged at the top while the molten iron
and slag are collected at the bottom and are tapped out at intervals.
(See Tin Plate Base Box)
A defect in metal produced by gas bubbles either on the surface
or formed beneath the surface while the metal is hot or plastic.
Very fine blisters are called “pin-head” or “pepper” blisters.
(Slab, Billet, Sheet-Bar.) Semifinished products, hot rolled
from ingots. The chief differences are in their cross sectional
areas in ratio of width to thickness, and in their intended use.
A mill used to reduce ingots to blooms, billets, slabs, sheet-bar
etc. (See Semi-Finished Steel)
A cavity produced during the solidification of metal by evolved
gas, which in failing to escape is held in pockets.
A process of softening ferrous alloys in the form of hot rolled
sheet, by heating in the open furnace to a temperature within
the transformation range and then cooling in air. The formation
of bluish oxide on the surface is incidental.
Reduced ductility occurring as a result of strain aging, when
certain ferrous alloys are worked between 300° and 700°F.
This phenomenon may be observed at the working temperature or
subsequently at lower temperatures.
(See Tempered Spring Steel Strip)
(1) Sheets - A method of coating sheets with a thin, even film
of bluish-black oxide, obtained by exposure to an atmosphere
of dry steam or air, at a temperature of about 1000 0øF.,
generally this is done during box-annealing. (2) Bluing of tempered
spring steel strip; an oxide film blue in color produced by low
temperature heating.
(Concerning space lattices.) Having the equivalent lattice
points at the corners of the unit cell, and at its center; sometimes
called centered or space-centered.
The coating of steel with a film composed largely of zinc phosphate
in order to develop better bonding surface for paint or lacquer.
(Chemical Symbol B)- Element No. 5 of the periodic system.
Atomic weight 10.82. It is gray in color, ignites at about 1112°F.
and burns with a brilliant green flame, but its melting point
in a non-oxidizing atmosphere is about 4000°F. Boron is used
in steel in minute quantities for one purpose only - to increase
the hardenability as in case hardening and to increase strength
and hardness penetration.
Ingot mold, with the top constricted; used in the manufacture
of “capped steel,” the metal in the constriction being
covered with a cap fitted into the bottleneck, which stops “rimming” action
by trapping escaping gases.
(See Camber)
A process of annealing a ferrous alloy in a suitable closed
metal container, with or without packing materials, in order
to minimize oxidation. The charge is usually heated slowly to
a temperature below the transformation range, but sometimes above
or within it, and is then cooled slowly. This process is also
called “close annealing” or “pot annealing.” (See
Black Annealing)
A piece of equipment used for bending sheet: also called a “bar
folder.” If operated manually, it is called a “hand
brake”; if power driven, it is called a “press brake.”
A diamond penetrator, conical in shape, used with a Rockwell
hardness tester for hard metals.
Strip. 70% copper 30% zinc. This is one of the most widely
used of the copper-zinc alloys; it is malleable and ductile;
has excellent cold-working; poor hot working and poor machining
properties; develops high tensile strength with cold-working.
Temper is impaired by cold rolling and classified in hardness
by the number of B & S Gages of rolling (reduction in thickness)
from the previous annealing gage. Rated excellent for soft-soldering;
good for silver alloy brazing or oxyacetylene welding and fair
for resistance of carbon arc welding. Used for drawn cartridges,
tubes, eyelet machine items, snap fasteners, etc.
(See SHIM)
Strip. 65% copper and 35% zinc. Known as “High Brass” or “Two
to One Brass.” A copper-zinc alloy yellow in color. Formerly
widely used but now largely supplanted by Cartridge Brass.
Copper base alloys in which zinc is the principal added element.
Brass is harder and stronger than either of its alloying elements
copper or zinc; it is malleable and ductile; develops high tensile
with cold-working and not heat treatable for purposes of hardness
development.
Joining metals by fusion of nonferrous alloys that have melting
points above 800°F. but lower than those of the metals being
joined. This may be accomplished by means of a torch (torch brazing),
in a furnace (furnace brazing) or by dipping in a molten flux
bath (dip or flux brazing). The filler metal is ordinarily in
rod form in torch brazing; whereas in furnace and dip brazing
the work material is first assembled and the filler metal may
then be applied as wire, washers, clips, bands, or may be integrally
bonded, as in brazing sheet.
(For tempered steel) A method of testing hardened and tempered
high carbon spring steel strip wherein the specimen is held and
bent across the grain in a vice-like calibrated testing machine.
Pressure is applied until the metal fractures at which point
a reading is taken and compared with a standard chart of brake
limitations for various thickness range. (See Bend Test)
The cold working of dead soft annealed strip metal immediately
prior to a forming, bending, or drawing operation. A process
designed to prevent the formulation of Luder’s lines. Caution:
Bridled metal should be used promptly and not permitted to (of
itself) return to its pre-bridled condition.
Steel wire bright drawn and annealed in controlled non-oxidizing
atmosphere furnace.
A process of annealing usually carried out in a controlled
furnace atmosphere so that surface oxidation is reduced to a
minimum and the surface remains relatively bright.
Bright steel wire, slightly softer than Bright Bessemer Wire.
Used for round head wood screws, bolts and rivets, electric welded
chain, etc.
Stiff bright steel wire of hard drawn temper. Normally drawn
to size without annealing. Used for nails, flat head wood screws,
cheap springs, etc.
(See Finishes)
An acid solution into which articles are dipped to obtain a
clean, bright surface.
A common standard method of measuring the hardness of certain
metals. The smooth surface of the metal is subjected to indentation
by a hardened steel ball under pressure or load. The diameter
of the resultant indentation, in the metal surface, is measured
by a special microscope and the Brinell hardness value read from
a chart or calculated formula.
A tendency to fracture without appreciable deformation.
Multiple shaving, accomplished by pushing a tool with stepped
cutting edges along the work, particularly through holes.
Primarily an alloy of copper and tin but the name is now applied
to other alloys not containing tin; e.g., aluminum, bronze, manganese
bronze, and beryllium bronze. For varieties and uses of tin bronze
see (Alpha Bronze and Phosphor Bronze).
A standard series of sizes arbitrarily indicated, as by numbers,
to which the diameter of wire or thickness of sheet metal is
usually made and which is used in the manufacture of brass, bronze,
copper, copper-base alloys and aluminum. These gage numbers have
a definite relationship to each other. By this system the decimal
thickness is reduced by 50% every six gage numbers -while temper
is expressed by the number of B S gage numbers as cold reduced
in thickness from previous annealing. For each B & S gage
number in thickness reduction, there is assigned a hardness value
of ¼ hard. To illustrate: One number hard = ¼ hard,
two numbers hard = ½ hard, etc.
Alternate bulges or hollows recurring along the length of the
product with the edges remaining relatively flat.
Heating a metal beyond the temperature limits allowable for
the desired heat treatment, or beyond the point where serious
oxidation or other detrimental action begins.
A term applied to a metal permanently damaged by overheating.
A thin ridge or roughness left by a cutting operation such
as in metal slitting, shearing, blanking or sawing. This is common
to a No. 3 slit edge in the case of steel.
A hardened, tempered, and bright polished high carbon spring
steel strip (carbon content a bit higher than in wood band saw
quality) with a Rockwell value of approximately C47/49.
Joining two edges or ends by placing one against the other
and welding them.
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