Q – T

Quality

Refers to the suitability and integrity of the steel for the purpose or purposes for which it is intended.

Quarter Hard (No. 3 Temper)
(A) In low carbon cold-rolled strip steel, a medium soft temper produced by a limited amount of cold rolling after annealing. (B) In brass mill terminology. Quarter hard is one B and S number hard or 10.95% reduction. (C) In stainless steel terminology tempers are based on minimum tensile, or yield strength. For Chromium-Nickel grades Quarter Hard Temper is 125,000 T. S., 75,000 Y.S. min.

Quench Aging
Aging that occurs after quenching following solution heat treatment.

Quench and Temper

This thermal treatment is the primary one used for hardening carbon, alloy, and martensitic stainless steels. It involves heating the metal above a critical temperature (austenitizing), and then cooling rapidly in a suitable medium (quenching). The metal is then reheated to a temperature below the critical temperature (tempering) to achieve the desired combination of hardness, ductility, and toughness.

Quench Hardening
Hardening by austenitizing and then cooling at a rate such that a substantial amount of austenite is transformed to martensite.

Quenching
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.

Radiant Tube Annealing Box
A box which is heated, inside, by means of tubes in which gas is burned; the hot tubes radiate their heat to the covered pile of metal, standing on the base of the box. Usually a protective atmosphere is maintained in the box to protect the metal from oxidation.

Radiography
A nondestructive method of internal examination in which metal objects are exposed to a beam of X-ray or gamma radiation. Differences in thickness, density or absorption, caused by internal defects or inclusions, are apparent in the shadow image either on a fluorescent screen or on photographic film placed behind the object.

Ragged Edges
Edges of Sheet or Strip which are torn, split, cracked, ragged or burred or otherwise disfigured.

Random Length

Tubing produced to a permissible variation in length. (Frequently seven feet).

Recarburizing
(1) Increasing the carbon content of molten cast iron or steel by adding carbonaceous material, high-carbon pig iron or a high-carbon alloy. (2) Carburizing a metal part to return surface carbon lost in processing.

Reciprocal Lattice (for a crystal)
A group of points arranged about a center in such a way that the line joining each point of the center is perpendicular to a family of planes in the crystal, and the length of this line is inversely proportional to their interplanar distance.

Recovery
Reduction or removal of work-hardening effects, without motion of large-angle grain boundaries.

Recrystallization
(1) The change from one crystal structure to another, as occurs on heating or cooling through a critical temperature. (2) The formation of a new, strain-free grain structure from that existing in cold worked metal, usually accomplished by heating.

Recrystallization Temperature
The approximate minimum temperature at which complete recrystallization of a cold worked metal occurs within a specified time.

Recystallization Annealing
Annealing cold worked metal to produce a new grain structure without a phase change.

Red Brass
85% Copper — A copper-zinc alloy containing approximately 15% zinc, used for plumbing pipe, hardware, condenser tubes. Because of its color, is used or vanity cases, coins, plaques, badges, etc. It is somewhat stronger than commercial bronze and is hardened more rapidly by cold working.

Red Shorness
Brittleness in steel when it is red hot.

Reducing Medium

A substance such as an acid that causes a chemical reaction in nickel alloys and other metals.

Reduction of Area
(1) Commonly, the difference, expressed as a percentage of original area, between the original cross-sectional area of a tensile test specimen and the minimum cross-sectional area measured after complete separation. (2) The difference, expressed as a percentage of original area, between original cross-sectional area and that after straining the specimen.

Refining Temperature
A temperature, usually just higher than the transformation range, employed in the heat treatment of steel to refine the structure — in particular, the grain size.

Reflector Sheet
An alclad product containing on one side a surface layer of high-purity aluminum superimposed on a core or base alloy of commercial-purity aluminum or an aluminum-manganese alloy. The high-purity coating imparts good polishing characteristics and the core gives adequate strength and formability.

Refractory
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.

Refractory Metal
A metal having an extremely high melting point. In the broad sense, it refers to metals having melting points above the range of iron, cobalt, and nickel.

Rephosphorizing (Steel)
A Ladle-chemical treatment consisting of the addition of phosphorus as a work hardening agent when temper rolling black plate or sheet steel resulting in greater hardness and stiffness and with a corresponding loss in ductility. . NOTE: Black Plate in tempers T5 and T6 (R/B range 68/84) are temper rolled from Rephosphorized steel.

Residual Elements
Small quantities of elements unintentionally present in an alloy.

Residual Stress
Macroscopic stresses that are set up within a metal as the result of non-uniform plastic deformation. This deformation may be caused by cold working or by drastic gradients of temperature from quenching or welding.

Residuals
‘Incidental’ or ‘tramp’ elements not named in a specification. These inclusions are usually due to contaminated scrap.

Resilience
The tendency of a material to return to its original shape after the removal of a stress that has produced elastic strain.

Resistance Welding
A type of welding process in which the work pieces are heated by the passage of an electric current through the contact. Such processes include spot welding, seam or line welding and percussion welding. Flash and butt welding are sometimes considered as resistance welding processes.

Resolution
The capacity of an optical or radiation system to separate closely spaced forms or entities; also, the degree to which such forms or entities can be discriminated.

Resulfurized Steel
Steel to which sulfur has been added in controlled amounts after refining. The sulfur is added to improve machinability.

Ribbon Wound
A term applied to a common method of winding strip steel layer upon layer around an arbor or mandrel.

Riffles
Waviness at the edge of sheet or strip.

Rimmed Steel
A low-carbon steel containing sufficient iron oxide to give a continuous evolution of carbon monoxide while the ingot is solidifying, resulting in a case or rim of metal virtually free of voids. Sheet and strip products made from the ingot have very good surface quality.

Ripple (defect)
A slight transverse wave or shadow mark appearing at intervals along the piece.

RMS

Measures the “smoothness” of a product. Standing for “root mean square”, the RMS number represents the depth of grooves in the surface of a metal. The lower the RMS, the smoother the metal.

 

Rockwell Hardness (HRB or HRC)

Rockwell is a method of measuring the hardness of materials. Hardness, in this sense, means resistance to penetration. The test gets its name from the Rockwell Corporation that built the original machines to do this. Rockwell measures the hardness by pressing an indentor into the surface of the steel with a specific load and then measuring how far the indentor was able to penetrate. While there are a number of Rockwell tests, the most common is Rockwell B. Rockwell C is used on hard materials. When the material is very thin, lighter loads must be used, resulting in Rockwell 30T, 15T, Rockwell 15-N, 30-N scales. There are conversion charts that will allow conversion from one method of hardness to another, but it must be remembered that these conversion charts cannot precisely convert from one to another. Unfortunately, most customers do not recognize that there are different Rockwell tests and/or do not realize that conversion charts are not totally accurate.

Rockwell Hardness Number

The number expressed to indicate the hardness and Rockwell scale used for the Rockwell Hardness Test.

Roll Forming
An operation used in forming sheet. Strips of sheet are passed between rolls of definite settings that bend the sheet progressively into structural members of various contours, sometimes called molded sections.

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.

Rolled In Scale
A surface defect consisting of scale partially rolled into the surface of the sheet.

Roller Leveling
Passing sheet or strip metal through a series of staggered small rolls so as to flatten the metal. This method is relatively ineffective in removing defects such as buckles, wavy edges, corrugations, twists, etc., or from steel in the higher hardness ranges.

Rolling
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 (in rolled metal)
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 the contours of which determine or fashion the product into numerous intermediate and final shapes, e.g., blooms, slabs, rails, bars, rods, sections, plates, sheets and strip.

Rotary Shear (Slitting Machine)
A cutting machine with sharpened circular blades or disc-like cutters used for trimming edges and slitting sheet and foil. NOTE: cutter discs are also employed in producing dircles from flat sheets but with differently designed machines.

Roto-Rock (Tube Reducing or Rockrite)

A method of cold finishing tubing in which a machine rolls or rocks a split die over a tube. The tube is supported on the inside by a tapered mandrel.

Rough Machining
Machining without regard to finish, usually to be followed by a subsequent operation.

Rough Turned

A bar having undergone stock removal to improve surface finish and size tolerances.

Rule Die Steel
A hardened and tempered medium high carbon spring steel strip sufficiently low in hardness to take moderately sharp bends without fracture, intended for manufacture into rule dies for the purpose of cutting or stamping fabrics, paper, cardboard, plastics, and metal foil into desired shape.

SAE
Abbreviation for 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. The last two digits always indicate the carbon content, usually within 0.05%.

Salt Spray Test
An accelerated corrosion test in which the metal specimens are exposed to a fine mist of salt water solution either continuously or intermittently.

Scab
A defect consisting of a flat volume of metal joined to a casting through a small area. It is usually set in a depression, a flat side being separated from the metal of the casting proper by a thin layer of sand.

Scab (scabby)
A blemish caused on a casting by eruption of gas from the mold face, or by uneven mold surfaces; or occurring where the skin from a blowhole has partly burned away and is not welded.

Scale
A layer of oxidation products formed on a metal at high temperature.

Scaling
(1) Oxidation of metal due to heat, resulting in relatively heavy surface layers of oxide. (2) Removal of scale from metal.

Scalped Extrusion Ingot
A cast, solid, or hollow extrusion ingot which has been machined on the outside surface.

Scalping
Machining the surface layers from ingots, billets and slabs before fabrication.

Scarf Joint
A butt joint in which the plane of the joint is inclined with respect to the main axes of the members.

Scarfing
Cutting surface areas of metal objects, ordinarily by using a gas torch. The operation permits surface defects to be cut from ingots, billets, or the edges of plate that is to be beveled for butt welding.

Scleroscope Hardness (Test)
A method for measuring the hardness of metals; a diamond-pointed hammer drops from a fixed distance through a tube onto the smoothed metal surface and the rebound measured. The scleroscope hardness value is empirically taken from the rebound distance, with a specified high-carbon steel as 100.

Scleroscope Test
A hardness test where the loss in kinetic energy of a falling metal tup, absorbed by indentation upon impact of the tup on the metal being tested, is indicated by the height of rebound.

Scrap
Material unsuitable for direct use but usable for reprocessing by re-melting.

Scratch Brushed Finish
Finish obtained by mechanically brushing the surface with wire bristle brushes, by buffing with greaseless compound or by cold rolling with wire bristled rolls on scratch etched finish.

Seam
On the surface of metal, an unwelded ford or lap which appears as a crack, usually resulting from a defect obtained in casting or in working.

Seamless (SMLS)

Tubing or pipe without a seam or weld.

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.

Secondary Hardening
Tempering certain alloy steels at certain temperatures so that the resulting hardness is greater than that obtained by tempering the same steel at some lower temperature for the same time.

Seconds
The designation given to sheet or strip that has imperfections in moderate degree or extent, which may be classified in two general groups — imperfections in the base material, or other manufacturing defects. This term not used in connection with non-ferrous alloys.

Segment Steel
Used for laminated piston rings. Carbon content about .60%. Hardened and blue tempered with round edges. Hardness usually Rockwells 30 N 68 to 71, widths vary from .058 to .163 and thicknesses are .020, .024 and .030.

Segregation
Nonumiform distribution of alloying elements, impurities or microphases.

Segregation
In an alloy, concentration of alloying elements at specific regions, usually as a result of the primary crystallization of one phase with the subsequent concentration of other elements in the remaining liquid.

Segregation Banding
In homogeneous distribution of alloying elements aligned on filaments or plates parallel to the direction of working.

Self Diffusion
The spontaneous movement of an atom to a new site in a crystal of its own species.

Self-Hardening Steel
A steel containing sufficient carbon or alloying element, or both, fo form martensite either through air hardening or, as in welding and induction hardening, through rapid removal of heat from a locally heated portion by conduction into the surrounding cold metal.

Semi-Steel
Cast iron (not steel) of high quality, obtained by using a large percentage of steel scrap with the pig iron.

Semifinished Steel
Steel in the form of billets, blooms, itc., requiring further working before completion into finished steel ready for marketing.

Semikilled Steel
Steel incompletely deoxidized, to permit evolution of sufficient carbon monoxide to offset solidification shrinkage.

Sendzimir Mill
A mill having two work rolls of 1 to 2 1/2-in diam. each, backed up by two rolls twice that diameter and each of these backed up by bearings on a shaft mounted eccentrically so that rotating it increases the pressure between bearings and backup rolls.

Sensitization

When sensitized, a stainless steel is susceptible to intergranular corrosion. Sensitization occurs when the stainless is heated through the temperature range of 800 to 1650oF. Chromium carbides precipitate at the grain boundaries, depleting chromium from adjacent areas and thereby reducing corrosion resistance.

Shear
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.

Shear Bands (deformation)
Bands in which deformation has been concentrated inhomogeneously in sheets that extend across regional groups of grains. Usually only one system is present in each regional group of grains, different systems being present in adhoining groups. The bands are noncrystallographic and form on planes of maximum shear stress (55(degrees) to the compression direction). They carry most of the deformation at large strains. Compare microbands.

Shear Crack
A diagonal, transgranular crack caused by shear stresses.

Shear Steel
Steel produced by forge welding together several bars of blister steel, providing a more homogeneous product.

Shear Strength
The stress required to produce fracture in the plane of cross section, the conditions of loading being such that the directions of force and of resistance are parallel and opposite although their paths are offset a specified minimum amount.

Sheet
A flat-rolled metal product of some maximum thickness and minimum width arbitrarily dependent on the type of metal. Sheet is thinner than plate.

Shell Molding
Forming a mold from thermosetting resin-bonded sand mixtures brought in contact with pregeated (300 to 500 (degrees) F) metal patterns, resulting in a firm shell with a cavity corresponding to the outline of the pattern. Also called Croning process.

Shielded-Arc Welding
Arc welding in which the arc and the weld metal are protected by a gaseous atmosphere, the products of decomposition of the electrode covering, or a blanket of fusible flux.

Shim
A thin flat hard metal strip produced to close tolerances; used primarily for tool, die and machine alignment purposes. In steel there are four general types: (1) Low Carbon Rockwell B 80/100; (2) Hard Rolled High Carbon Rockwell C 28/33. (3) Hardened and Tempered Spring Steel Rockwell C 44/51; (4) Austenitic Stainless Steel Rockwell C 35/45. Brass shim of commercial quality is also used and most generally specified is 2 Nos. Hard but may be 4 Nos. Hard.

Shore Hardness Test
Same as scleroscope test.

Short
Brittle.

Short Terne
A term applying to terne coated (Lead and Tin) sheets with reference to Base Box sizes (14 x 20) Refer to terne plate.

Shortness
A form of brittleness in metal. It is designated as cold, hot, and red, to indicate the temperature range in which the brittleness occurs.

Shot Blasting
Cleaning surface of metal by air blast, using metal as a result of solidification shrinkage and the progressive freezing of metal towards the center.

Shrinkage Cavity
A void left in cast metals as a result of solidification shrinkage and the progressive freezing of metal towards the center.

Sigma Phase

A chemical compound of iron, chromium and molybdenum. When this occurs, corrosion resistance is reduced as the chromium and molybdenum are not available for that purpose.

Silicon
Chemical symbol Si. Element No. 14 of the periodic system; atomic weight 28.06. Extremely common element, the major component of all rodks and sands; its chemical reactions, however, are those of a metalloid. Used in metallurgy as a deoxidizing scavenger. Silicon is present, to some extent, in all steels, and is deliberately added to the extent of approximately 4% for electric sheets, extensively used in alternating current magnetic circuits. Silicon cannot be electrodeposited.

Silicon Steel
Steel usually made in the basic open-hearth or electric furnace, with about 0.50-5.% silicon, other elements being usually dept as low as possible. Because of high electrical resistance and low hysterisis loss, silicon sheet and strip are standard in electric magnet manufacture.

Siliconizing
Diffusing silicon into solid metal, usually steel, at an elevated temperature.

Silky Fracture
A steel fracture that has a very smooth fine grain or silky appearance.

Silver Solders
Alloys of silver, copper, sinc and other metals, melting between 650 and 875 (degrees) C. used for making strong yet moderately ductile joints that resist corrosion.

Single-Action Press
A forming press that operates with a single function, such as moving a punch into a die with no simultaneous action for holding down the bland or ejecting the formed work.

Sink Drawing

Sink drawn tubing is produced by drawing the welded tube through a die with only the O.D. being controlled. This question is performed when closer tolerances or a better surface might be required on the O.D. only and for enhanced mechanical properties. Sink drawn tubing can be produced from either hot rolled or cold rolled steel and I.D. flash can be any of the conditions described above.

Sinker Steel
Used for making sinkers in hosiery making machinery. Supplied both hardened and tempered and cold rolled and annealed. Usually extra precision rolled and extra flat. Carbon content about 1.25.

Sinkhead or Hot Top
A reservoir insulated to retain heat and to hod excess molten metal on top of an ingot mold, in order to feed the shrinkage of the ingot. Also called shrink head or feeder head.

Sintered Carbide
Composite, containing carbides of extremely refractory metals, such as tungsten, tantalum, titanium, etc., cemented together by a relatively low-melting metal, such as cobalt acing as a matrix.

Sintering
Converting powder into a continuous mass by heating to a temperature considerably below fusion, usually after preliminary compacting by pressure.

Skelp
A piece or strip of metal produced to a suitable thickness, width, and edge configuration, from which pipe or tubing is made.

Skelp
A plate of steel or wrought iron from which pipe or tubing is made by rolling the skelp into shape longitudinally and welding or riveting the edges together.

Skin
A thin surface layer that is different from the main mass of a metal object, in composition, structure or other characteristics.

Skull
A layer of solidified metal or dross on the wall of a pouring vessel often when metal has been poured.

Slab
A piece of metal, intermediate between ingot and plate, at least twice as wide as it is thick.

Slack Quenching
The process of hardening steel by quenching from the austenitizing temperature at a rate slower than the critical cooling rate for the particular steel, resulting in incomplete hardening and the formation of one or more transformation products in addition to or instead of martensite.

Slag
A nonmetallic product resulting form mutual dissolution of flux and nonmetallic impurities in smelting and refining operations.

Sliding Abrasion

The continuous wearing force against a metal’s surface by an abrasive.

Slip
Plastic deformation by irreversible shear displacement of one part of a crystal relative to another in a definite crystallographic direction and on a definite crystallographic plane.

Slip Direction
The crystallographic direction in which translation of slip takes place.

Slip Line
Trace of a slip plane on a viewing surface.

Slip Plane
The crystallographic plane on which slip occurs in a crystal.

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

Slitting
Cutting sheet or strip metal to width by rotary slitters.

Sliver (defect)
Loose metal piece rolled down onto the surface of the metal during the rolling operations.

Soaking
Prolonged heating of a metal at selected temperature.

Soaking Pit

A furnace or pit for the heating of ingots of steel to make their temperature uniform prior to rolling or forging.

 

Soft Skin Rolled Temper (No. 4 Temper)
In low carbon-rolled strip steel, soft and ductile. Produced by subjecting annealed strip to a pinch pass or skin rolling (a very light rolling).

Solder Embrittlement
Reduction in ductility of a metal or alloy, associated with local penetration by molten solder along grain boundaries.

Soldering
Joining metals by fusion of alloys that have relatively low melting points — most commonly, lead-base or tin-base alloys, which are the soft solders. Hard solders are alloys that have silver, copper, or nickel bases and use of these alloys with melting points higher than 800 (degrees) F. is generally termed brazing.

Solid Solution
A single solid homogeneous crystalline phase containing two or more chemical species.

Solidus
In a constitutional diagram, the locus of points representing the temperatures at which various components finish freezing on cooling or begin to melt on heating.

Solute
The component of either a liquid or solid solution that is present to the lesser or minor extent; the component that is dissolved in the solvent.

Solution Heat Treatment
A heat treatment in which an alloy is heated to a suitable temperature, held at that temperature long enough to cause one or more constituents to enter into solid solution, and then cooled rapidly enough to hold these constituents in solution.

Solution Treating

While the same thermal process as solution annealing, it is performed on age hardenable grades of nickel alloys and makes the result of the subsequent age hardening much more predictable and uniform.

Solvent
The component of either a liquid or solid solution that is present to the greater or major extent; the component that dissolves the solute.

Solvus
In a phase or equilibrium diagram, the locus of points representing the temperature at which solid phases with various compositions coexist with other solid phases; that is, the limits of solid solubility.

Sorbite
Structure of steel, resulting from the tempering of martensite. In a truly sorbitic structure, the cementite is completely dispersed in the matrix. The trend is to call this structure tempered martensite.

Sorbite (obsolete)
A fine mixture of ferrite and cementite produced either by regulating the rate of cooling of steel or tempering steel after hardening. The first type is very fine pearlite difficult to resolve under the microscope; the second type is tempered martensite.

Sorbitic Pearlite
Structure of steel resulting, on cooling under the proper conditions, from the decomposition of austenite; has a fine, lamellar appearance.

Space Lattice (crystal)
A system of equivalent points formed by the intersections of three sets of planes parallel to pairs of principal axes; the space lattice may be thought of as formed by the corners of the unit cells.

Space-Centered (concerning space lattices)
Body-centered.

Spalling
The cracking and flaking of particles out of a surface.

Special Smooth I.D. (S.S.I.D.)

A cold drawn tube in which special attention is paid to the internal surface. Depth of pits and scores in I.D. are guaranteed to be below published maximum depths. Microinch finish is guaranteed in ERW tubes.

Specification

A document defining the measurements, test, and other requirements to which a product must conform – typically covering chemistry, mechanical properties, tolerances, finish, reports, marking and packaging.

Specific Gravity
A numerical value representing the weight of a given substance as compared with the weight of an equal volume of water, for which the specific gravity is taken as 1.0000.

Spectograph
An optical instrument for determining the presence or concentration of minor metallic constituents in a material by indicating the presence and intensity of specific wave lengths of radiation when the material is thermally or electrically excited.

Spelter (Prime Western Spelter)
A low-grade of Virgin Zinc containing approximately 98% Zinc used in Galvanizing processes.

Speroidizing Annealing
A subcritical annealing treatment intended to produce spheroidization of cementite or other carbide phases.

Spheroidized Structure
A microstructure consisting of a matrix containing spheroidal particles of another constituent.

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

Spheroidizing
Heating and cooling to produce a spheroidal or globular form of carbide in steel.

Spiegel
High-manganese pig iron, containing 15-30% manganese, approximately 5% carbon, and less than 1% silicon used in the manufacture of steel by the Bessemer, or basic open-hearth process.

Spinning
The procedure of making sheet metal discs into hollow shapes by pressing the metal against a rotating form (spinning chuck) by a tool.

Spot Welding
An electric-resistance welding process in which the fusion is limited to a small area. The pieces being welded are pressed together between a pair of water-cooled electrodes through which an electical current is passed during a very short interval so that fusion occurs over a small area at the interface between the pieces.

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 required 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.

Spring-Back
An indicator of elastic stresses, frequently measured as the increase in diameter of a curved strip after removing it from the mandrel about which it was held. The measurement is employed as an indicator of the extent of recovery or relief of residual stresses that has been achieved by the transformation of elastic strain to plastic strain during heating or stress relieving.

Stabilizing

A phenomenon peculiar to the 5XXX series or magnesium-bearing alloys, which tend to age soften during storage. The resultant lowering of mechanical properties may cause the metal to be below spec when the customer uses it. To prevent this, most of these products are subjected to low temperature thermal treatment before they are shipped from the mill. The result of this treatment is a slight drop in the metal’s yield tensile strength to a stable level that is no longer subject to age softening.

Stabilizing Anneal
A treatment applied to austentic stainless steels that contain titanium or columbium. 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 columbium 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, atmospheric oxidation, etc.

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

Standard Gold
A legally adopted alloy for coinage of gold. In the United States the alloy contains 10% Cu.

Steel
An iron-base alloy, malleable in some temperature range as initially cast, containing maganease, usually carbon, and often other alloying elements. In carbon steel and low-alloy steel, the maximum carbon is about 2.0%; in high-alloy steel, about 2.5%. The dividing line between low-alloy and high-alloy steels is generally regarded as being at about 5% metallic alloying elements. Steel is to be differentiated from two general classes of irons: the cast irons, on the high-carbon side, and the relatively pure irons such as ingot iron, carbonyl iron, and electrolytic iron, on the low-carbon side. In some steels containing extremely low carbon, the maganese content is the principal differentiating factor, steel usually containing at least 0.25%; ingot iron contains considerably less.

Sterling Silver
A silver alloy containing at least 95.2% Ag, the remainder being unspecified but usually copper.

Sticker
Steel sheets or strip adhering. Usually by fusion spots caused by overheating during box annealing.

Straight-Chrome
An iron alloy. A term indicating a group of stainless steels the principal alloying element of which is chromium in varying amounts from 4.00 to 27.00%.

Strain
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.

Streamline Tubing

Extruded or drawn tubing of which the cross section is shaped like a teardrop.

Strength

Expressed as tensile or yield. Refers to the metal’s resistance to deformation or fatigue.

Stress
Force per unit area. True stress denotes stress determined by measuring force and area at the same time. Conventional stress, as applied to tension and compression tests, is force divided by original area. Nominal stress is stress computed by simple elasticity formula.

Stress Relieving
Heating to a suitable temperature, holding long enough to reduce residual stresses and then cooling slowly enough to minimize the development of new residual stresses.

Stress-corrosion Cracking
Failure by cracking under the combined action of corrosion and stress, either external (applied) or internal (residual). Cracking may be either intergranular or transgranular, depending on the metal and the corrosive medium.

Stress-Rupture Test
A tension test performed at constant temperature, the load being held at such a level as to cause rupture. Also known as creep-rupture test.

Stretch Forming
A process of forming panels and cowls of large curvature by stretching sheet over a form of the desired shape. This method is more rapid than hammering and beating.

Stretch Reduce

A technique employed in the manufacture of CW pipe in which one or several master sizes of pipe are produced, then stretched reduced through a number of rolls to achieve a variety of pipe diameters. Also used in certain instances in seamless and ERW manufacturing.

Stretcher Leveling
A method of making metal sheet or strip dead flat by stretching.

Stretcher Straightening
A process for straightening rod, tubing, and shapes by the application of tension at the ends of the stock. The products are elongated a definite amount to remove warpage.

Stretcher Strains
Elongated markings that appear on the surface of some materials when deformed just past the yield point. These markings lie approximately parallel to the direction of maximum shear stress and are the result of localized yielding Same as Luders lines.

Strip Steel (cold rolled)
A flat cold rolled steel product (Other than Flat Wire) 23 15/16 and narrower; under .250 in thickness, which has been cold reduced to desired decimal thickness and temper on single stand, single stand reversing, or tandem cold mills in coil form from coiled hot rolled pickled strip steel.

Structural Tubing

Tubing used primarily for structural applications and produced in squares, rectangles, rounds and shapes.

Sub-boundary Structure (subgrain structure)
A network of low-angle boundaries (usually with misorientations or less than one degree) within the main grains of a microstructure.

Subcritical Annealing
An annealing treatment in which a steel is heated to a temperature below the A1 temperature and then cooled slowly to room temperature.

Subgrain
A portion of a crystal or grain slightly different in orientation from neighboring portions of the same crystal. Generally, neighboring subgrains are separated by low-angle boundaries.

Substrate
The layer of metal underlying a coating, regardless of whether the layer is base metal.

Sulfide Spheroidization
A stage of overheating in which sulfide inclusions are partly or completely spheroidized.

Sulfide Stress Cracking

A severe potentially catastrophic failing that appears as branching transangular cracks in Austenitic stainless. Caused by a combination of tensile stress, corrosive media, temperature, and lack of oxygen. Preventive measures include increasing or decreasing the nickel content, removing stresses, and using duplex stainless.

Sulfur
Chemical symbol S) Element No. 16 of the periodic system; atomic weight 32.06. Non-metal occurring in a number of allotropic modifications, the most common being a pale-yellow brittle solid. In steel most commonly encountered as an undesired contaminant. However, it is frequently deliberately added to cutting stock, to increase machinability.

Sulfur Print
A macrographic method of examining distribution of sulfide inclusions.

Sunk or Sink Drawn

Tubing drawn through a die with no inside mandrel to control I.D. or wall thickness.

Superalloy
An alloy developed for very high temperature service where relatively high stresses (tensile, thermal, vibratory, and shock) are encountered and where oxidation resistance is frequently required.

Supercooling
Cooling to a temperature below that of an equilibrium phase transformation without the transformation taking place.

Superficial Rockwell Hardness Test
Form of Rockwell hardness test using relatively light loads which produce minimum penetration. Used for determining surface hardness or hardness of thin sections or small parts, or where large hardness impression might be harmful.

Superheating
(1) Heating a phase to a temperature above that of a phase transformation without the transformation taking place. (2) Heating molten metal to a temperature to obtain more complete refining or greater fluidity.

Surface Hardening
A generic term covering several processes applicable to a suitable ferrous alloy that produce, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are induction hardening, flame hardening and shell hardening. Use of the applicable specific process name is preferred.

Swaging

A method of cold working tubing in which the reduction is accomplished by hammering tubing to the desired dimension. The hammer blows are delivered rapidly against the outside surface of the tube. An inside mandrel may or may not be used.

T & C

Threaded and coupled.

Tack Welds
Small scattered welds made to hold parts of a weld in proper alignment while the final welds are being made.

Tandem Mill
Arrangement of rolling mills, in direct line, allowing the metal to pass from one set of rolls into the next.

Tantalum

A hard, ductile, gray-white metallic element used as a stabilizing agent in stainless steels and nickel alloys.

Taper Section
A section made at an acute angle to a surface of interest, thereby achieving a geometrical magnification of depth. A sectioning angle 5(degrees) 43 achieves a depth magnification of 10: 1.

Tapping
Transferring molten metal from melting furnace to ladle.

Tarnish
Surface discoloration on a metal, usually from a thin film of oxide or sulfide.

Teeming
Pouring metal into ingot molds.

Telescoping
Transverse slipping of successive layers of a coil so that the edge of the coil is conical rather than flat.

Temper (Met.)
The state of or condition of a metal as to its hardness or toughness produced by either thermal treatment or heat treatment and quench or cold working or a combination of same in order to bring the metal to its specified consistency. Each branch of the metal producing industry has developed its own system of temper designations. In flat-rolled products including sheet and strip steel, tin mill products, stainless strip, aluminum sheet and copper base alloy strip they are shown as follows

Temper Brittleness
Brittleness that results when certain steels are held within, or are cooled slowly through, a certain range of temperature below the transformation range. The brittleness is revealed by notched-bar impact tests at or below room temperature.

Temper Rolling
Light cold rolling of sheet steel. The operation is performed to improve flatness, to minimize the formation of stretcher strains, and to obtain a specified hardness or temper.

Tempered and Polished Spring Steel Strip
90/1.03 carbon range (Also known as clock spring steel.) This product, while similar to general description under heading of Tempered Spring Steel Strip, is manufactured and processed with great and extreme care exercised in each step of its production. Manufactured from carbon range of .90/1.03 with Rockwell range C 48/51. Clock spring quality has been ground and polished with edges dressed. It is usually supplied hard blue in color and has a wide range of uses, such as coiled and flat mechanical springs, ignition vibrator springs, springs for timing devices, springs for the electric and electonic fields, steel tapes, rules, etc.

Tempered Spring Steel Strip
Any medium or high carbon (excluding clock spring) strip steel of spring quality which has been hardened and tempered to meet specifications. Where specification calls for blue or straw color, same is accomplished by passing through heat prepared at proper temperature depending on color required. Blue is developed at approximately 600 (degrees) F.

Tempering
In heat treatment, re-heating hardened steel to some temperature below the A1 temperature for the purpose of decreasing hardness and/or increasing toughness. The process also is sometimes applied to normalized steel.

Tensile Strength (Also called ultimate strength)
Breaking strength of a material when subjected to a tensile (stretching) force. Usually measured by placing a standard test piece in the jaws of a tensile machine, gradually separating the jaws, and measuring the stretching force necessary to break the test piece. Tensile strength is commonly expressed as pounds (or tons) per square inch of original cross section.

Tensile Test

The three results usually reported are: 1. Yield Point – the stress at which there is a marked increase in deformation without a proportional increase in load. 2. Tensile Strength – the maximum load observed during the test before breakage occurs. 3. Elongation – the amount that a specified gage length containing the fracture has stretched during the test, expressed as a percentage.

Ternary Alloy
An alloy that contains three principal elements.

Terne Plate
Sheet steel, coated with a lead-tin alloy. The percentage of tin is usually kept as low as possible because of its high cost; however, about 15% is normally necessary in order to obtain proper coating of the steel, since pure lead does not alloy with iron and some surface alloying is necessary for proper adhesion.

Texture
In a polycrystalline aggregate, the state of distribution of crystal orientations. In the usual sense, it is synonymous with preferred orientation, in which the distribution is not random.

Thermal Analysis
A method of studying transformations in metal by measuring the temperatures at which thermal arrests occur.

Thermal Treatment

Cycles of heating, holding and cooling metal to achieve desired results.

Thermocouple
A device for measuring temperatures by the use of two dissimilar metals in contact; the junction of these metals gives rise to a measurable electrical potential with changes in temperature.

Thickness Gage or Feeler Stock
A hardened and tempered, edged, ground, and polished thin section, high carbon strip steel. Usually 1/2 in width and in thicknesses from .001 to .050 manufactured to extremely close tolerances. It is used primarily for determining measurement of openings by tool and die makers, machinists, and automobile technicians. It is prepared in handy pocket size knife-like holders containing an assembly of various thicknesses. Also prepared in standard 12 lengths with rounded ends and in 10 ‘ and 25’ coils. Universally used in the metal industry.

Three-Quarter Hard Temper
(A) In stainless steel strip tempers are based on a minimum tensile or yield strength. For Chromium-Nickel grades three-quarter hard temper is 175,000 T.S., 135,000 Y.S. min. (B) In Brass mill terminology, this temper is three B&S numbers hard or 29.4% thickness reduction.

Tin
Chemical symbol Sn. Element No. 50 of the periodic system; atomic weight 118.70. Soft silvery white metal of high malleability and ductility, but low tensile strength; melting point 449 (degrees) F., boiling point 4384 (degrees) F., yielding the longest molten-state range for any common metal; specific gravity 7.28. Principal use as a coating on steel in tin plate; also as a constituent in alloys.

Tin Plate Base Box
A Tin Plate Base Box is measured in terms of pounds per Base Box (112 sheets 14 x 20) a unit peculiar to the tin industry. This corresponds to it’s area of sheet totaling to 31.360 square inches of any gage and is applied to tin plate weighing from 55 to 275 pounds per base box. To convert to decimal thickness multiply weight per base box by .00011.

Tin Plating
Electroplating metal objects with tin; the object to be coated is made cathode (negative electrode) in an electrolytic bath containing a decomposable tin salt.

Tinning
Coating with tin, commonly either by immersion into molten tin or by electro-deposition; also by spraying.

Titanium
Chemical symbol Ti. Element No. 22 of the periodic system; atomic weight 47.90; melting point about 3270 (degrees) F.; boiling point over 5430 (degrees) F.; specific gravity 4.5. Bright white metal, very malleable and ductile when exceedingly pure. Its principal functions as an alloy in the making of steel. (1) Fixes carbon in inert particles (a) reduces martensitic hardness and hardnability in medium chromium steels. (b) prevents formation of austenite in high-chromium steels. (c) prevents localized depletion of chromium in stainless steel during long heating. Now finding application in its own right because of its high strength and good corrosion resistance.

Tolerance

The leeway a producer is allowed in making an item to specified di­mensions. It is virtually impossible for met­al producers to manufacture Items to the exact dimensions specified and permissi­ble deviations are published and are ex­pressed as plus (+) or minus (-), oversize or undersize. Always keep in mind that the total deviation is the sum of those two fig­ures. Thus, a bar which has a diameter tolerance of +.003″ or – .003″ may have a total spread of .006″.

Tolerance Limit
The permissible deviation from the desired value.

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

Torsion
A twisting action resulting in shear stresses and strains.

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

Trace
Extremely small quantity of an element, usually too small to determine quantitatively.

Transformation
A constitutional change in a solid metal, e.g., the change from gamma to alpha iron, or the formation of pearlite from austenite.

Transformation Range
Temperature range over which a chemical or metallurgical change takes place.

Transformation Temperature
The temperature at which transformation occurs. The term is sometimes used to denote the limiting temperature of a transformation range.

Transverse
Literally, ‘across’, usually signifying a direction or plane perpendicular to the direction of working.

Transverse Properties

This term refers to mechanical properties measured perpendicular to the direction of rolling.

Tread Sheet & Plate

This product has a raised one-side diamond embossed pattern imparted by mill rolls to provide improved traction. It is often misidentified as “Tread Sheet”, belying the fact that it is commonly produced in plate thickness also. For years, 6061 was the standard alloy for this product, but several of the non-heat-treatable alloys are now also available in this pattern. The latter, under the heading of “Tread Bright”, finds applications where aesthetics is more important to the user than strength.

Trepanning
A type of boring where an annular cut is made into a solid material with the coincidental formation of a plug or solid cylinder.

Triple Point
The intersection of the boundaries of three adjoining grains, as observed in a section.

Trowel Steel
Hardened and tempered spring steel. .90 to 1.05 carbon content. Ordinary tolerances, but rolled extra flat — Rockwell C 50. Used in the manufacture of plastering trowels.

Truss Spring Steel
Supplied cold rolled and bright annealed. Carbon content about .70 — Manganese .74. Must be formed very severely and must be as free as possible from decarburization.

Tube

A hollow wrought product that is long in relation to its cross section, is round, hexagonal, octagonal, elliptical, square or rectangular with sharp or rounded corners and has uniform wall thickness except as affected by corner radii. Like pipe, tube may or may not have seams or welds depending on the method of manufacture. There are three common designations used to describe the dimensions and weight of tubing: OD (outside diameter); ID (inside diameter); and Wall (wall thickness).

Tube Hollow

As a generic term for any ERW…SMLS or CDBW tube ready for further processing…such as cold drawing.

Tube Reducer

A machine in which a pair of rolls is used for cold rolling tubing and rod. These rolls have a tapered groove around part of their surface, corresponding to the intended change in outside dimension of the tube or rod. The stock is rotated between working strokes. This process is somewhat different from the Pilger process in that the stock moves in the same direction, as rolling proceeds; the axes of the rolls moves back and forth parallel to the stock; and the direction of rotation of the rolls changes between the forward working stroke and the backward return stroke. A fixed mandrel is used in rolling tubing.

Tube Reducing

A method of cold working tubular products in which a pair of rolls having tapered grooves is rolled and reciprocated along the outside of the tube so that reduction of diameter and wall thickness is accomplished against a fixed, tapered mandrel or the inside of the tube. Roll reliefs at the initial and final diameters permit advance and rotation of the tube with each cycle. (It is used primarily on stainless seamless tubing.)

Tube Round

A term used to describe a seamless product ready to be shipped. Also sometimes used instead of tube hollow.

Tubing

A non-standardized hollow shaped product with a relatively uniform wall thickness, generally round, square or rectangular and manufactured to specified requirements for dimensions, chemical analysis, mechanical properties and other characteristics (such as surface) required for applications in aircraft, sanitary, mechanical, pressure, ornamental or structural uses. It is generally specified to two dimensions, i.e., O.D. (outside diameter) and wall, I.D. (inside diameter) and wall, or O.D. and I.D. It is not primarily designed for used with standard threaded pipe couplings or for applications where standard or heavy wall pipe is normally used.

Tukon Hardness Test
A method for determining microhardness by using a Knoop diamond indenter or Vickers square-base pyramid indenter.

Tumbling
Cleaning articles by rotating them in a cylinder with cleaning materials.

Tungsten
Chemical symbol W. Element No. 74 of the periodic system; atomic weight 183.92. Gray metal of high tensile strength, ductile and malleable when specially handled. It is immune to atmospheric influences and most acids, but not to strong alkalis. The metal is used as filament and in thin sheet form in incandescent bulbs and radio tubes. (1) Forms hard abrasion — resistant particles in tool steels. (2) Promotes hardness and strength at elevated temperatures.

Tungsten Carbide
Compound of tungsten and carbon, of composition varying between WC and W(2)C; imbedded in a matrix of soft metal, such as cobalt, extensively used for Sintered Carbide Tools.

Tungsten Inert Gas (TIG) Welding

A variation of the electric resistance welded method. It is used for most stainless steel products. Although the process is similar to that of ERW, TIG welding is a slower process whereby gas is used along with electricity to increase the heat and protect the material from oxidation while it is being fused.

Turkshead

Consists of a frame, mounted on a draw bench, containing four rolls with their axes at right angles and so positioned as to provide an opening corresponding to the section to be formed: round tubes are pulled through the rolls without internal mandrel support. The outside corners of sections processed by these means do not have constant radii.

Turning

A method for removing the surface from a work piece by bringing the cutting edge of a tool against it while the piece or tool is rotated.

Twin
Two portions of a crystal having a definite orientation relationship; one may be regarded as the parent, the other as the twin. The orientation of the twin is either a mirror image of the orientation of the parent across a twinning plane or an orientation that can be derived by rotating the twin portion about a twinning axis.

Twin, Annealing
A twin produced as the result of heat treatment.

Twin, Crystal
A portion of a crystal in which the lattice is a mirror image of the lattice of the remainder of the crystal.

Twin, Deformation
A twinned region produced by a shear like distortion of the parent crystal structure during deformation. In ferrite, deformation twins form on {211} planes.

Twist
A winding departure from flatness.