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Age Hardening:

The gradual changes that take place in properties of soft or low-carbon steels after the final treatment, which bring about increased hardness, elasticity and tensile strength after the steel has returned to normal temperatures.


The spontaneous change in the physical properties of some metals, which occurs on standing at atmospheric temperatures after final cold working or heat treatment.

Air Cooling:

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.

Air Hardening Steel:

Alloy steel that may be hardened by cooling in air from a temperature above the transformation range.

AISI Steels:

Steels of the American Iron and Steel Institute.


The common name for a type of clad-wrought aluminum products with coatings of high-purity aluminum or an aluminum alloy different from the core alloy in composition. The coatings are anodic to the core so they protect exposed areas on the core electrolytically during exposure to corrosive environments.


A metal made by adding other metals and nonmetals to a basic a basic metal to secure desirable properties.

Alloy Steel:

Steel containing substantial quantities of elements other than carbon for the purpose of increased hardness, strength or chemical resistance. The most common metals used for forming alloys are nickel, chromium, silicon, manganese, tungsten, molybdenum and vanadium.


A metal that is ductile and malleable; stable against normal atmospheric corrosion, but attacked by both acids and alkalis. It is used extensively in articles requiring lightness, corrosion resistance, electrical conductivity.


A heating and cooling operation implying a relatively slow cooling; the process is used to remove stresses; to induce softness; to alter ductility; toughness; electrical, magnetic or other physical properties; to refine the crystalline structure; to remove gases; or to produce a definite microstructure.

Artificial Aging:

An aging treatment above room temperature.


Formerly known as the American Society for Testing and Materials, an international organization that issues standards specifications for materials, including metals and alloys.


A phase in certain steels, characterized as a solid solution, usually of carbon or iron carbide, in the gamma form of iron.

Austenitic Steel:

Steel which, due to the presence of alloying elements like manganese, nickel or chromium, shows stability of austenite at normal temperatures.

Bath Annealing:

Immersion in a liquid bath, such as molten lead or fused salts, held at an assigned temperature.

Beryllium Copper:

An alloy of copper and 2%-3% beryllium with nickel or cobalt, which shows remarkable age-hardening properties and good electrical conductivity; often used in electrical switches and springs.

Blast Furnace:

A vertical shaft-type smelting furnace in which a hot air blast is used for producing pig iron.


Semi-finished products, hot rolled from ingots.


A mill used to reduce ingots to blooms, billets, slabs, sheet-bar, etc.


A copper-zinc alloy yellow in color; known as “High Brass” or “Two-to-One Brass.”


Joining metals by fusion of nonferrous alloys that have melting points above 800°F but lower than those of the metals being joined.

Bright Annealed Wire:

Steel wire bright drawn and annealed in controlled nonoxidizing atmosphere furnace.

Bright Annealing:

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.

Brinell Hardness Test:

A common standard method of measuring the hardness of certain metals by which the smooth surface of the metal is subjected to indentation by a hardened steel ball under pressure or load. The diameter of the resulting indentation is measured by a special microscope.


A tendency to fracture without appreciable deformation.


An alloy of copper and tin.


A thin ridge or roughness left by a cutting operation such as in metal slitting, shearing, blanking or sawing.

Butt Welding:

Joining two edges or ends by placing one against the other and welding them.


A compound of carbon with one or more metallic elements.


An element on the periodic table that is present in nearly all ferrous alloys and has tremendous effect on the properties of the resultant metal.

Carbon Free:

Metals and alloys that have practically no carbon.

Carbon Range:

In steel specifications, the difference between the minimum and maximum amount of carbon acceptable.

Carbon Steel:

Common or ordinary steel as contrasted with special or alloy steels, which contain other alloying metals in addition to the usual constituents of steel in their common percentages.


The addition of carbon to the surface of iron-base alloys by absorption through heating the metal at a temperature below its melting point in contact with carbonaceous solids, liquids or gases.

Case Hardening:

Carburizing and subsequently hardening by suitable heat treatment, all or part of the surface portions of a piece of iron-base alloy.

Cast Steel:

Any object made by pouring molten steel into molds.


A relatively hard metal, strongly resistant to oxidation and corrosion, which makes it of great value in the manufacture of stainless steel.

Chromium-Nickel Steel:

A steel in which chromium and nickel participate as alloying elements.

Clad Metal:

A composite metal containing two or three layers that have been bonded together.


A process for covering one metal with another in which the surfaces of two fairly thick slabs of metals are brought carefully into contact and are then subjected to co-rolling.


A gray magnetic metal of medium hardness with good corrosion resistance; it principally functions as an alloy in tool steel.


A flat sheet or strip metal that is coiled, usually in one continuous piece or length.

Cold Reduced Strip:

Metal strip, made from hot-rolled strip, by rolling on cold-reduction mills.

Cold Reduction:

The reduction of metal size, usually by rolling or drawing particularly thickness, while the metal is maintained at room temperature or below the recrystallization temperature of the metal.

Cold Rolled Finish:

A finish obtained by cold rolling a plain pickled sheet or strip with a lubricant, resulting in a smooth appearance.

Cold Rolling:

Rolling metal at a temperature below the softening point of the metal to create work hardening.

Cold Working:

Plastic deformation at a temperature sufficiently low to create work-hardening.


Also known as niobium, this element is used mainly in the production of austenitic chromium-nickel steels and to reduce the air-hardening characteristics in plain chromium steels.

Commercial Bronze:

A copper-zinc alloy containing 90% copper and 10% zinc; commonly used for screws, wire and hardware.

Commercial Quality Steel Sheet:

A standard quality carbon steel sheet.

Continuous Casting:

A casting technique in which the ingot is continuously solidified while it is being poured and the length is not determined by mold dimensions.


A reddish metal that is highly malleable and ductile and has high electrical and heat conductivity.


Gradual chemical or electrochemical attack on a metal by atmosphere, moisture or other agents.

Cross Direction:

The direction at, right angles, to the direction of rolling or drawing.

Dead Soft Annealing:

The heating of metal to above the critical range and appropriately cooling to develop the greatest possible commercial softness or ductility.

Dead Soft Steel:

A steel normally made in the basic open-hearth furnace or by the basic oxygen process with carbon less than 0.10% and manganese in the 0.20%-0.50% range and which is completely annealed.

Dead Soft Temper:

Condition of maximum softness commercially attainable in wire, strip, or sheet metal in the annealed state.


A method whereby the raw slit edge of metal is removed by rolling or filing.


The removal of carbon from the outer surface of iron or steel, usually by heating in an oxidizing or reducing atmosphere.

Deep Drawing:

The process of cold working sheet or strip metal blanks by means of dies on a press into shapes, which are usually cuplike in character and involving considerable plastic deformation of the metal.

Drill Rod:

An annealed and polished high alloy steel rod that is usually round.

Dry Rolled Finish:

A finish obtained by cold rolling on polished rolls without the use of any coolant or metal lubricant, material previously plain pickled, giving a burnished appearance.


The property of metals that enables them to be mechanically deformed when cold without fracturing.


The side produced in the manufacture of flat rolled metal products.


An increase in length that occurs when a metal is subjected to stress but has not fractured.

Eutectoid Steel:

A steel that contains 0.9% carbon.

Expander Steel:

Steel that has been hardened, tempered and blue polished; often used for the expanders in oil piston rings.

Extra-Hard Temper:

In brass mill terminology, Extra Hard is six numbers hard or 50.15% reduction from the previous annealing or soft stage.

Extra-Spring Temper:

In brass mill terminology, Extra Spring is ten numbers hard or 68.55% reduction in thickness from the previous annealing or soft stage.


Shaping metal into a chosen continuous form by forcing it through a die of appropriate shape.


Relating to iron.


The surface appearance of the various metals after final treatment.

Finishing Temperature:

Temperature of final hot working of a metal.

Flame Annealing:

A process of softening a metal by the application of heat from a high-temperature flame.

Flame Hardening:

A process of hardening a ferrous alloy by heating it above the transformation range by means of a high-temperature flame, and then cooling as required.

Flat Wire:

A flat cold-rolled, prepared-edge section up to .25″ wide, rectangular in shape.


Metal in any width but no more than about 0.005″ thick.


Surface appearance of metals when broken.

Fracture Test:

Nicking and breaking a bar by means of sudden impact, to enable macroscopic study of the fracture.

Full Annealing:

Used principally on iron and steel, means heating the metal to about 100°F above the critical temperature range, followed by “soaking” and slow cooling below the critical temperature.

Full Finish Plate:

Steel sheet or strip reduced either hot or cold, cleaned, annealed and then cold-rolled to a bright finish.

Full Hard Temper:

In low carbon sheet or strip steel, stiff and springy, not suitable for bending in any direction. It is the hardest temper obtainable by hard cold rolling.


Manufacturers’ standard numbering systems indicating decimal thickness or diameters.


The damaging of one or both metallic surfaces by removal of particles from localized areas due to seizure curing sliding friction.


A solid many-sided crystal consisting of groups of atoms bound together in a regular geometric pattern. In mill practice grains are usually studied only as they appear in one plane. In steel, the ductility in the direction of rolling is almost twice that at right angles to the direction of rolling.

Grain Boundary:

Bounding surface between crystals. When alloys yield new phases, grain boundaries are the preferred location for the appearance of the new phase. Certain deteriorations, such as season cracking and caustic embrittlement, usually occur at grain boundaries.

Grain Growth:

An increase in metallic crystal size as annealing temperature is raised; growth occurs by invasion of crystal areas by other crystals.

Grain Size:

Average diameter of grains in the metal under consideration, or alternatively, the number of grains per unit area. Since increase in grain size is paralleled by lower ductility and impact resistance, the question of general grain size is of great significance.


Individual crystals in metals.

Ground Flat Stock:

Annealed and pre-ground tool steel flats in standard sizes ready for tool room use. These are three common grades: water hardening, oil hardening and air hardening quality.

Half Hard Temper:

In low carbon cold-rolled strip steel, produced by cold rolling to a hardness next to, but somewhat softer than, full hard temper. In brass stainless steel strip, tempers are based on minimum tensile or yield strength.

Hard Drawing:

Drawing metal wire through a die to reduce cross section and increase tensile strength.

Hard Drawn:

Wire or tubing drawn to high tensile strength by a high degree of cold work.

Hard Drawn Spring Steel Wire:

A medium high carbon cold drawn spring steel wire. Used principally for cold springs.


The ability of a metal, usually steel, to harden in depth as distinguished from the term “hardness.”

Hardened And Tempered Spring Steel Strip:

A medium or high carbon quality steel strip which has been subjected to the sequence of heating, quenching and tempering.


Any process which increases the hardness of a metal. Usually heating and quenching certain iron base alloys from a temperature either within or above the critical temperature range.


Degree to which a metal will resist cutting, abrasion, penetration, bending and stretching.

Heat Treatment:

Altering the properties of a metal by subjecting it to a sequence of temperature changes, time of retention at specific temperature and rate of cooling therefore being as important as the temperature itself. Heat treatment usually markedly affects strength, hardness, ductility, malleability and similar properties of both metals and their alloys.

Hot Working:

Plastic deformation of metal at a temperature sufficiently high not to create strain hardening. The lower limit of temperature for this process is the recrystallization temperature.

Impact Test:

Test designed to determine, the resistance of metal to breakage by impact, usually by concentrating the applied stress to a notched specimen.


Particles of impurities that are held mechanically or are formed during the solidification or by subsequent reaction within the solid metal.

Induction Hardening:

A process of hardening a ferrous alloy by heating it above the transformation range by means of electrical induction, and then cooling as required.


A casting for subsequent rolling or forging.

Intermediate Annealing:

An annealing treatment given to wrought metals following cold work hardening for the purpose of softness prior to further cold working.


A magnetic metal characterized by its high tensile strength, ductility and malleability.


A defect appearing in sheets or strips as a segregation or in layers.


Flattening rolled metal sheet or strip.

Light Metals:

Metals and alloys that have a low specific gravity, such as beryllium, magnesium and aluminum.

Low Carbon Steels:

Contain from 0.10% to 0.30% carbon and less than 0.60% manganese.

Macroetch Test:

Consists of immersing a carefully prepared section of the steel in hot acid and of examining the etching surface to evaluate the soundness and homogeneity of the product being tested.


The structure of metal as revealed by macroscopic examination.


A metal known for its low density, malleability, ductility and the white light it produces when burning.


The property that determines the ease of deforming a metal when the metal is subjected to rolling or hammering.


A brittle, non-malleable metal that is used in alloys to increase hardenability and counteract the brittleness from sulfur.

Mechanical Properties:

Those properties of a material that reveal the elastic and inelastic reaction when force is applied, or that involve the relationship between stress and strain; for example, the modulus of elasticity, tensile strength and fatigue limit.

Medium-Carbon Steel:

Contains from 0.30% to 0.60% carbon and less than 1.00% manganese.


The structure of polished and etched metal and alloy specimens as revealed by the microscope.

Mill Edge:

The edge of strip, sheet or plate in the as-rolled state.

Mill Finish:

A surface finish produced on sheet and plate.


A hard, tough metal that is very ductile and malleable when properly treated at high temperatures, deepens hardening, counteracts temper brittleness, enhances the corrosion resistance in stainless steel, and forms abrasion-resisting particles.


A slightly magnetic metal of medium hardness and high degree of ductility and malleability and resistance to chemical and atmospheric corrosion that is commonly used for electroplating or as an alloying agent.

Nickel Silver:

Copper base alloys that contain 10%-45% zinc and 5%-30% nickel.

Nickel Steel:

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.


Process of surface hardening certain types of steel by heating in ammonia gas at about 935-1,000°F.

Nitriding Steel:

Steel that is particularly suited for the nitriding process, that is, it will form a very hard and adherent surface upon proper nitriding.

Nonferrous Metals:

Metals or alloys that are free of iron.

Nonmetallic Inclusions:

Impurities held in metals mechanically during solidification or formed by reactions in the solid state.

Nonrefractory Alloy:

An alloy that has malleability or is easily flatten when rolled or hammered.


A heat treatment applied to steel that involves heating the metal above the critical range followed by cooling in still air.

Orange Peel:

A surface roughening defect resulting from using metal that has a coarse grain size. Also referred to as “pebbles” and “alligator skin.”


Aging under conditions of time and temperature greater than those required to obtain maximum strength.


The addition of oxygen to a compound. Exposure to atmosphere sometimes results in oxidation of the exposed surface, hence a staining or discoloration.


Compounding oxygen with another element.


Nickel alloys that containing about 20% to 60% of iron and are used for their high magnetic permeability and electrical resistivity.

Phosphor Bronze:

Copper base alloys to which phosphor has been added in the molten state for deoxidizing and strengthening purposes; known for its excellent toughness, strength, fine grain, resistance to fatigue and wear and chemical resistance.


A nonmetallic element that, in steels, increases strength and resistance to corrosion, and improves machinability.

Physical Properties:

Those properties familiarly discussed in physics, such as density or electrical conductivity.


The process of chemically removing oxides and scale from the surface of a metal by the action of water solutions of inorganic acids.

Plastic Deformation:

Permanent distortion of a material under the action of applied stresses.


The ability of a metal to be deformed extensively without rupture.


A thin coating of metal laid on another metal.

Polished Surface:

The finish obtained by buffing with rouge or similar fine abrasive, resulting in a high gloss or polish.

Powder Metallurgy:

The art of producing metal powders and of utilizing metal powders for the production of massive materials and shaped objects.

Precipitation Hardening:

A process of hardening an alloy in which a constituent precipitates from a supersaturated solid solution.

Precipitation Heat Treatment:

Any of the various aging treatments conducted at elevated temperature to improve certain of the mechanical properties through precipitation from solid solution.


A term used to describe heating applied as a preliminary to some further thermal or mechanical treatment.

Process Annealing:

In the sheet and wire industries, a process by which a ferrous alloy is heated to a temperature close to, but below, the lower limit of the transformation range and is subsequently cooled. This process is applied to soften the alloy for further cold working.

Progressive Aging:

An aging process in which the temperature of the alloy is continually increased during the aging cycle. The temperature may be increased in steps or by any other progressive method.

Quarter Hard:

A medium soft temper produced by a limited amount of cold rolling after annealing.

Quench Hardening:

A process of hardening a ferrous alloy of suitable composition by heating within or above the transformation range and cooling at a rate sufficient to increase the hardness substantially. The process usually involves the formation of martensite.


In the heat treating of metals, the step of cooling metals rapidly in order to obtain desired properties; most commonly accomplished by immersing the metal in oil or water. In the case of most copper base alloys, quenching has no effect other than to hasten cooling.

Reduction Of Area:

The percent of cross-sectional area the metal will “Neck Down” prior to breaking in tension.


A heat-resistant material, usually nonmetallic, which is used for furnace linings and such.

Refractory Alloy:

A term applied to those alloys which due to hardness or abrasiveness present relative difficulty in maintaining close dimensional tolerances.

Rockwell Hardness:

A standard method for measuring or testing the hardness of metals. The hardness is expressed as a number related to the depth of residual penetration of a steel ball or diamond cone after a minor load of 10 kilograms has been applied to hold the penetrator in position. This residual penetration is automatically registered on a dial when the major load is removed from the penetrator.

Rolled Edges:

Finished edges, the final contours of which are produced by side or edging rolls. The edge contours most commonly used are square corners, rounded corners and rounded edge.


A term applied to the operation of shaping and reducing metal in thickness by passing it between rolls which compress, shape and lengthen it following the roll pattern.

Rolling Direction:

The direction, in the plane of the sheet, perpendicular to the axes of the rolls during rolling.

Rolling Mills:

Equipment used for rolling down metal to a smaller size or to a given shape employing sets of rolls tie contours of which determine or fashion the product into numerous intermediate and final shapes.


Society of Automotive Engineers; this organization has specified common and alloy steels and copper base alloys in accordance with a numerical index system allowing approximation of the composition of the metal.


Oxidation of metal due to heat resulting in relatively heavy surface layers of oxide.


A crack on the surface of metal that has been closed but not welded; usually produced by some defect either in casting or in working.

Seam Welding:

An electric-resistance type of welding process, in which the lapped sheet is passed between electrodes of the roller type while a series of overlapping spot welds is made by the intermittent application of electric current.


A type of cutting operation in which the metal object is cut by means of a moving blade and fixed edge or by a pair of moving blades that may be either flat or curved.


A thin flat hard metal strip produced to close tolerances; used primarily for tool, die and machine alignment purposes.


An element that is present in all steels; known for high electrical resistance.

Silicon Steel:

Steel usually made with about 0.5%-5% silicon.

Slit Edges:

The edges of sheet or strip metal resulting from cutting to width by rotary slitters.


Cutting sheet or strip metal to width by rotary slitters.

Solution Heat Treatment:

A process in which an alloy is heated to a suitable temperature, is held at this temperature long enough to allow a certain constituent to enter into solid solution and is then cooled rapidly to hold the constituent in solution.


Any process of prolonged heating and slow cooling of steel which will convert the carbide content into rounded or spheroid form.

Spring Steel:

Steel, normally of the high-carbon or alloy type, used in the manufacture of springs, lending itself to appropriate heat treatment; usually made is the open hearth or electric furnace.

Spring Steel Strip:

Any of a number of strip steels produced for use in the manufacture of steel springs or where high tensile properties are requires marketed in the annealed state, hard rolled or as hardened and tempered strip.

Spring Temper:

In brass mill terminology, spring temper is eight numbers hard or 60.50% reduction.

Stabilizing Anneal:

A treatment applied to austenitic stainless steels that contain titanium or niobium. This treatment consists of heating to a temperature below that of a full anneal in order to precipitate the maximum amount of carbon at titanium carbide or niobium carbide. This eliminates precipitation at lower temperatures, which might reduce the resistance of the steel to corrosion.

Stabilizing Treatment:

A thermal treatment designed to precipitate material from solid solution, in order to improve the workability, to decrease the tendency of certain alloys to age harden at room temperature, or to obtain dimensional stability under service at slightly elevated temperatures.

Stainless Steel:

Corrosion resistant steel of a wide variety, but always containing a high percentage of chromium. These are highly resistant to corrosion attack by organic acids, weak mineral acids and atmospheric oxidation.


A term used to refer to various press forming operations in coining, embossing, blanking, and pressing.


Iron, malleable in at least one range of temperature below its melting point without special heat treatment substantially free from slag, and containing carbon more than about 0.05% and less than about 2.00%.


Deformation produced on a body by an outside force.

Strain Aging:

Aging induced by cold working.

Strain Hardening:

An increase in hardness and strength caused by plastic deformation at temperatures lower than the recrystallization range.


Deforming force to which a body is subjected or the resistance which the body offers to deformation by the force.

Stress Relief:

Low temperature annealing for removing internal stresses, such as those resulting in a metal from work hardening or quenching.

Stress Relieving:

Reducing residual stresses by heating.

Stretch Forming:

A process of forming panels and cowls of large curvature by stretching sheet over a form of the desired shape.

Stretcher Leveling:

A method of making metal sheet or strip perfectly flat by stretching. Also called “patent leveling.”

Stretcher Strains:

Long vein-like marks appearing on the surface of certain metals in the direction of the maximum shear stress, when the metal is subjected to deformation beyond the yield point.

Strip Steel:

A flat, cold-rolled steel product under .25″ in thickness.


The arrangement of parts; in crystals, especially the shape and dimension of the unit cell, and the number, kinds and positions of the atoms within it.


A nonmetal element that is frequently found as a contaminant in steel. It is, however, added to cutting stock to increase machinability.


The state of a metal relating to its hardness or toughness produced by thermal treatment, heat treatment and quench, or cold working to bring the metal to its specified consistency.

Tempered Spring Steel Strip:

Any medium or high carbon strip steel of spring quality which has been hardened and tempered to meet specifications. When polished, it is also called “clock spring steel”; it is been ground and polished with its edges dressed.


A process of reheating quench-hardened or normalized steel to a temperature below the transformation range and then cooling at any rate desired. The primary purpose of tempering is to impart a degree of plasticity or toughness to the steel to alleviate the brittleness of its martensite.

Tensile Strength:

The breaking strength of a material when subjected to a stretching force.


An element known for its high malleability and ductility, but low tensile strength. It is mainly used as a coating on steel in tin plate and in alloys.


An element known for its malleability and ductility when pure, and high strength and good corrosion resistance in alloys.

Tool Steel:

Any high carbon or alloy steel capable of being suitable tempered for use in the manufacture of tools.


Property of resisting fracture or distortion. Usually measured by impact test, high impact values indicating high toughness.


An element known for its high tensile strength, ductility, and malleability. It promotes hardness and strength at elevated temperatures.

Tungsten Carbide:

A compound of tungsten and carbon, it is frequently imbedded in soft metals, such as cobalt.


A metalworking operation similar to forging; or the process of axial flow under axial compression of metal, as in forming heads on rivets by flattening the end of wire.


An element frequently used in alloys to make tool steels. Its properties mean it elevates the coarsening temperature of austenite, increases hardenability and resists tempering.

Water Hardening:

The process of hardening high carbon steels by quenching in water or brine after heating.


The process used to join metals through heat. Fusion welding requires the parent metals be melted. Pressure welding uses heat and pressure without melting the metals.

Work Hardening:

The increase in resistance to deformation, which is produced by cold working of the metal.


The characteristic that determines the ease of forming a certain metal into shapes.

Yield Point:

The load per unit of original cross section at which, in soft steel, a marked increase in deformation occurs without increase in load.

Yield Strength:

The stress at which the metal changes from elastic to plastic in behavior.


An element that is used as a coating for steel. In alloys, especially in brass, it is used in die-casting.


An element that is used as a deoxidizer and scavenger in steelmaking. Bonds readily with nitrogen, sulfur and oxygen.