Spontaneous aging of a supersaturated solid solution at room temperature.
Local reduction of the cross-sectional area of metal by
Needle Cutter Steel
Usually supplied quarter hard rolled, extra
precision rolled with sheared edges. Carbon content 1.25 - Chromium .15. Usually
supplied in a 2 width from .002 to .035. Used for cutting the eyes of needle and
milling the latch in a latch needle.
A structure in which the crystals of one
constituent are surrounded by envelopes of another constituent which gives a
network appearance to an etched test specimen.
A fracture test in which a specimen is broken from a notch cut at a
predetermined position where the interior of the weld is to be examined.
(Chemical symbol Ni) Element No. 28 of the
periodic system; atomic weight 58.69. Silvery white, slightly magnetic metal, of
medium hardness and high degree of ductility and malleability and resistance to
chemical and atmospheric corrosion; melting point 2651 (degrees) F.; boiling
point about 5250 (degrees) F., specific gravity 8.90.
An alloying element used as a raw material for certain classes of stainless
steel. Nickel provides high degrees of ductility (ability to change shape
without fracture) as well as resistance to corrosion. Approximately 65% of all
nickel is used in the making of stainless steel.
Also used for electroplating.
Used as an alloying agent, it is of great importance in iron-base alloys in
stainless steels and in copper-base alloys such as Cupro-Nickel, as well as in
nickel-base alloys such as Monel Metal. Its principal functions as an alloy in
steel making: (1) Strengthens unquenched or annealed steels.
(2) Toughens pearlitic-ferritic steels (especially at low temperature).
high-chromium iron alloys austenitic.
Copper base alloys that contain 10-45% Zn.
and 5-30% Ni.
Steel containing nickel as an alloying
element. Varying amounts are added to increase the strength in the normalized
condition to enable hardening to be performed in oil or air instead of water.
(Chemical symbol Nb) Element No. 41 of the
Introducing nitrogen into a solid ferrous
alloy by holding at a suitable temperature (below Ac1 for ferritic steels) in
contact with a nitrogenous material, usually ammonia of molten cyanide of
appropriate composition. Quenching is not required to produce a hard case.
Process of surface hardening certain types of
steel by heating in ammonia gas at about 935-1000 (degrees) F., the increase in
hardness being the result of surface nitride formation. Certain alloying
constituents, principal among them being aluminum, greatly facilitate the
hardening reaction. In general, the depth of the case is less than with
Steel which is particularly suited for the
nitriding process, that is, it will form a very hard and adherent surface upon
proper nitriding (heating in a partially dissociated atmosphere of ammonia gas).
Composition usually .20-.40 carbon, .90-1.50 chromium, .15-1.00 molybdenum, and
Pearlite that has grown as a colony with an approximately spherical
No. 1 Heavy Melt
Obsolete steel scrap grade, at least
one-quarter inch in thickness and in sections no larger than five feet by two
feet. Much of the metal comes from demolished buildings, truck frames and heavy
duty springs. Mini-mills are primary consumers of No. 1 heavy scrap.
Metals or alloys that are free of iron or
Impurities (commonly oxides), sulphides, silicates or similar substances held in metals mechanically during solidification or formed by reactions in the solid state.
A term opposed to refractory alloy. A non-refractory alloy has malleability, that is, ease of flattening when subjected to rolling or hammering.
Strip steel ordered or sold on the basis of
absence of unevenness, or ears, on the edges of the steel, when subjected to
A heat treatment applied to steel, Involves
heating above the critical range followed by cooling in still air. Is performed
to refine the crystal structure and eliminate internal stress.
A measure of the susceptibility of a material
to brittle fracture at locations of stress concentration. For example, in a
notch tensile test a material is said to be notch brittle if its notch strength
is less than its tensile strength; otherwise, it is said to be notch ductile.
Notch (Impact) toughness
An indication of a steel's capacity to absorb energy when a stress
concentrator or notch is present. examples are Charpy V-Notch, dynamic
tear, drop-weight and drop-weight tear tests.
Number as Pertaining to Edge
Number as Pertaining to Hardness
In copper base alloys industry; temper is referred to as so many numbers hard, i.e.; Yellow Brass Half Hard is termed 2 numbers hard. This term is derived from terminology used on the mill floor whereby temper or hardness is imparted by cold working and classified as to hardness by the number of Brown & Sharpe gages away from the soft or as-annealed state.
Number as Pertaining to Temper