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 - Alloy A substance having metallic properties and composed of two or more chemical elements of which at least one is a metal.   Alloy Steel Steel containing substantial quantities of elements other than carbon and the commonly-accepted limited amounts of manganese, sulfur, silicon, and phosphorus. Addition of such alloying elements is usually for the purpose of increased hardness, strength or chemical resistance. The metals most commonly used for forming alloy steels are: nickel, chromium, silicon, manganese tungsten, molybdenum and vanadium, Low Alloy steels are usually considered to be those containing a total of less than 5% of such added constituents. Aluminizing Forming an aluminum or aluminum alloy coating on a metal by hot dipping, hot spraying, or diffusion. Aluminum (Chemical symbol Al) Element No. 13 of the periodic system; Atomic weight 26.97; silvery white metal of valence 3; melting point 1220 (degrees) F; boiling point approximately 4118 (degrees) F.; ductile and malleable; stable against normal atmospheric corrosion, but attacked by both acids and alkalis. Aluminum is used extensively in articles requiring lightness, corrosion resistance, electrical conductivity, etc. Its principal functions as an alloy in steel making; (1) Deoxidizes efficiently. (2) Restricts grain growth (by forming dispersed oxides or nitrides) (3) Alloying element in nitriding steel. Aluminum Killed Steel A steel where aluminum has been used as a deoxidizing agent. Angstrom Unit (A) A unit of linear measure equal to 10(-10)m, or 0.1 nm; not an accepted Si unit, but still sometimes used for small distances such as interatomic distances and some wavelengths. Annealing Heating to and holding at a suitable temperature and then cooling at a suitable rate, for such purposes as reducing hardness, improving machinability, facilitating cold working, producing a desired microstructure, or obtaining desired mechanical, physical, or other properties. When applicable, the following more specific terms should be used: black annealing, blue annealing, box annealing, bright annealing, flame annealing, graphitizing, intermediate annealing, isothermal annealing, malleablizing, process annealing, quench annealing, recrystallization annealing, and spheroidizing. When applied to ferrous alloys, the term annealing, without qualification, implies full annealing. When applied to nonferrous alloys, the term annealing implies a heat treatment designed to soften an age-hardened alloy by causing a nearly complete precipitation of the second phase in relatively coarse form. Any process of annealing will usually reduce stresses, but if the treatment is applied for the sole purpose of such relief, it should be designated stress relieving. Artificial Aging An aging treatment above room temperature. ASTM Abbreviation for American Society For Testing Material. An organization for issuing standard specifications on materials, including metals and alloys. Ausenitic Grain Size The size of the grains in steel heated into the austenitic region. Austenite Phase in certain steels, characterized as a solid solution, usually of carbon or iron carbide, in the hamma form of iron. Such steels are known as austenitic. Austenite is stable only above 1333 (degrees) F. in a plain carbon steel, but the presence of certain alloying elements, such as nickel and manganese, stabilizes the austenitec form, even at normal temperatures. Austenitic Steel Steel which, because of the presence of alloying elements, such as manganese, nickel, chromium, etc., shows stability of Austenite at normal temperatures. Austenitizing Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing).   Austentite A solid solution of one or more elements in face-centered cubic iron. Basic Steel Steel melted in a furnace with a basic bottom and lining and under a slag containing an excess of a basic substance such as magnesia or lime.      << Top >>     - B - Bend Radius The inside radius of a bent section, Bend Test Various tests which is used to ascertain the toughness and ductility of a metal product, in which the material is bent around its axis and/ 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 employed, then you must line the jaws with some soft metal, to permit a flow of the metal in the piece being tested. Blister A defect in metal, on or near the surface, resulting from the expansion of gas in a subsurface zone. Very small blisters are called pinheads or pepper blisters. Blue Annealing Heating hot rolled ferrous sheet in an open furnace to a temperature within the transformation range and then cooling in air, in order to soften the metal. The formation of a bluish oxide on the surface is incidental. Blue Brittleness Reduced ductility occurring as a result of strain aging, when certain ferrous alloys are worked between 300 and 700 (degrees) F. This phenomenon may be observed at the working temperature or subsequently at lower temperatures. Bonderizing The coating of steel with a film composed largely of zinc phosphate in order to develop a better bonding surface for paint or lacquer. Box Annealing Annealing a metal or alloy in a sealed container under conditions that minimize oxidation. In box annealing a ferrous alloy, 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. Box Annealing A process of annealing a ferrous alloy in a closed metal container, with or without packing materials, in order to minimize the effects of oxidation. The charge is normally heated slowly to a temperature below the transformation range, but occasionally above or within it, and then is slowly cooled. Break Test (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 ranges. Bridling 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. Brinell Hardness Test A common standard method of measuring the hardness of materials. The smooth surface of the metal is subjected to indentation by a hardened steel ball under pressure. The diameter of the indentation, in the material surface, is then measured by a microscope and the hardness value is read from a chart or determined by a prescribed formula. Brittle Fracture Fracture preceded by little or negligible plastic deformation. Brittleness The tendency of a metal or material to fracture without undergoing appreciable plastic deformation. Broaching Multiple shaving, accomplished by pushing a tool with stepped cutting edges along the piece, particularly through holes. Buckle Bulges and/ or hollows occurring along the length of the metal with the edges remaining otherwise flat. Burning (1) Permanently damaging a metal or alloy by heating to cause either incipient melting or intergranular oxidation. (2) In grinding getting the work hot enough to cause discoloration or to change the microstructure by tempering or hardening. Burnishing Smoothing surfaces through friction between the material and material such as hardened metal media. Burr Roughness left by a cutting operation such as slitting, shearing, blanking , etc. Butt Welding Joining two edges or ends by placing one against the other and welding them.    << Top >> - C - Camber or Bow Edgewise curvature. A lateral departure of a side edge of sheet or strip metal from a straight line.   Carbon Chemical symbol C. Element No. 6 of the periodic system; atomic weight 12.01; has three allotropic modifications, all non-metallic. Carbon is present in practically all ferrous alloys, and has tremendous effect on the properties of the resultant metal. Carbon is also an essential component of the cemented carbides. Its metallurgical use, in the form of coke, for reduction of oxides, is very extensive. Carbon Equivalent Referring to the rating of weld-ability, this is a value that takes into account the equivalent additive effects of carbon and other alloying elements on a particular characteristic of a steel. For rating of weld-ability, a formula commonly used is: CE = C + (Mn/6) + [(Cr + Mo + V)/5] + [(Ni + Cu)/15].   Carbon Free Metals and alloys which are practically free from carbon.   Carbon Steel A steel containing only residual quantities of elements other than carbon, except those added for deoxidization or to counter the deleterious effects of residual sulfur. Silicon is usually limited to about 0.60% and manganese to about 1,65%. Also termed plain carbon steel, ordinary steel, straight carbon steel.   Carbonitriding Introducing carbon and nitrogen into a solid ferrous alloy by holding above Ac1 in an atmosphere that contains suitable gases such as hydrocardons, carbon monocide, and ammonia. The carbonitrided alloy is usually quench hardened.   Cast Steel Steel in the form of castings, usually containing less than 2% carbon.   Charpy Test A pendulum-type single-blow impact test in which the specimen usually notched, is supported at both ends as a simple beam and broken by a falling pendulum. The energy absorbed, as determined by the subsequent rise of the pendulum, is a measure of impact strength or notch toughness.   Chromium Chemical symbol Cr. Element No. 24 of the periodic system; atomic weight 52.01. It is of bright silvery color, relatively hard. It is strongly resistant to atmospheric and other oxidation. It is of great value in the manufacture of Stainless Steel as an iron-base alloy. Chromium plating has also become a large outlet for the metal. Its principal functions as an alloy in steel making; (1) increases resistance to corrosion and oxidation (2) increases harden-ability (3) adds some strength at high temperatures (4) resists abrasion and wear (with high carbon).   Coil Breaks Creases or ridges across a metal sheet transverse to the direction of coiling, occasionally occurring when the metal has been coiled hot and uncoiled cold.   Coil Weld A joint between two lengths of metal within a coil - not always visible in the cold reduced product. Cold Reduced Strip Metal strip, produced from hot-rolled strip, by rolling on a cold reduction mill. Corrosion Deterioration of a metal by chemical or electrochemical reaction with its environment. Cup Fracture (Cup-and-Cone Fracture) Fracture, frequently seen in tensile test pieces of a ductile material, in which the surface of failure on one portion shows a central flat area of failure in tension, with an exterior extended rim of failure in shear.   << Top >>   - D - Decarburization Removal of carbon from the outer surface of iron or steel, usually by heating in an oxidizing or reducing atmosphere. Water vapor, oxygen and carbon dioxide are strong decarburizers. Reheating with adhering scale is also strongly decarburizing in action. Deoxidizing Removal of oxygen. In steel sheet, strip, and wire technology, the term refers to heat treatment in a reducing atmosphere, to lessen the amount of scale. Drawing Back Reheating after hardening to a temperature below the critical for the purpose of changing the hardness of the steel.   Ductility The property of metals that enables them to be mechanically deformed when cold, without fracture. In steel, ductility is usually measured by elongation and reduction of area as determined in a tensile test.   << Top >>   - E - Eddy-Current Testing Nondestructive testing method in which eddy-curent flow is induced in the test object. Changes in the flow caused by variations in the object are reflected into a nearby coil or coils for subsequent analysis by suitable instrumentation and techniques.     << Top >>   - F - Fatigue The phenomenon leading to fracture under repeated or fluctuating stresses having a maximum value less than the tensile strength of the material. Fatigue fractures are progressive, beginning as minute cracks that grow under the action of the fluctuating stress.   Ferrite A solid solution of one or more elements in body-centered cubic iron. Unless otherwise designated (for instance, as chromium ferrite), the solute is generally assumed to be carbon. On some equilibrium diagrams ther are two ferrite regions separated by an austenite area. The lower area is alpha ferrite; the upper, delta ferrite. If there is no designation, alpha ferrite is assumed. Foil Metal in any width but no more than about 0.005 thick. Fracture Test Nicking and breaking a bar by means of sudden impact, to enable macroscopic study of the fractured surface.   Full Annealing Used principally on iron and steel, means heating the metal to about 100 (degrees) F. above the critical temperature range, followed by soaking at this point and slow cooling below the critical temperature. Full Hard Temper (A) (No. 1 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. (B) In Stainless Steel Strip, tempers are based on minimum tensile or yield strength. For Chromium-Nickel grades Full Hard temper is 185,000 TS, 140,000 YS Min. Term also used in connection with copper base alloys and considered synonymous with Hard Temper.   << Top >>   - G - Gages Mfrs. standard numbering systems indicating decimal thickness' or diameters.   Galvanizing Coating steel with zinc and tin (principally zinc) for rust proofing purposes. Formerly for the purpose of galvanizing, cut length steel sheets were passed singly through a bath of the molten metal. Today's galvanizing processing method consists of uncoiling and passing the continuous length of successive coils either through a molten bath of the metal termed Hot Dipped Galvanizing or by continuously zinc coating the uncoiled sheet electrolytically- termed Electro-Galvanizing. Grain A solid polyhedral (or 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. (1) (Direction of) Refers to grain fiber following the direction of rolling and parallel to edges of strip or sheets. (2) To bend across the grain is to bend at right angles to the direction of rolling. (3) To bend with the grain is to bend parallel to the direction of rolling. In steel, the ductility in the direction of rolling is almost twice that at right angles to the direction of rolling. Grain Size (1) For metals, a measure of the areas or volumes of grains in a polycrystalline material, usually expressed as an average when the individual sizes are fairly uniform. Grain sizes are reported in terms of grains per unit area or volume, average diameter, or as a grain-size number derived form area measurements.   << Top >>     - H - Half Hard Temper (A) In low carbon cold-rolled strip steel, produced by cold rolling to a hardness next to but somewhat softer than full hard temper. (B) In brass mill terminology, half hard is two B&S numbers hard or 20.70% thickness reduction. (C) In Stainless Steel Strip, Tempers are based on minimum tensile or yield strength. For Chromium-Nickel grades Half-Hard Temper 150,000 T.S., 110,000 Y.S.Min.   Hard Chromium Chromium deposited for engineering purposes, such as increasing the wear resistance of sliding metal surfaces, rather than as a decorative coating. It is usually applied directly to basis metal and is customarily thicker than a decorative deposit.   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. Hardening Increasing hardness by suitable treatment, usually involving heating and cooling. When applicable, the following more specific terms should be used: age hardening, case hardening, flame hardening, induction hardening, precipitation hardening, quench hardening.   Hardness (indentation) Resistance of a metal to plastic deformation by indentation. Various hardness tests such as Brinell, Rockwell and Vickers may be used. In the Vickers test, a diamond pyramid with an included face angle of 136 is used as the indenter.   Hot Dip In steel mill practice, a process wherby ferrous alloy base metals are dipped into molten metal, usually zinc, tin, or terne, for the purpose of fizing a rust resistant coating. Hot Short Brittleness in hot metal. Hot Shortness Brittleness in metal in the hot forming range.   << Top >>   - I - Impact Energy (Impact Value) The amount of energy required to ffracture a material, usually measured by means of an Izod or Charpy test. The type of speciment and testing conditions affect the values and therfore should be specified.   Impact Test Test designed to determine the resistance of metal to breakage by impact, usually by concentrating the applied stress to a notched specimen. .Indentation Hardness The resistance of a meterial to indentation. This is the usual type osf hardness test, in which a pointed or rounded indenter is pressed into a surface under a substantially static load.   Interleaving The placing of a sheet of paper between two adjacent layers of metal to facilitate handling and shearing of rectangular sheets, or to prevent sticking or scratching   Internal Oxidation Formation of oxides beneath the surface of a metal. Interrupted Aging The aging of an alloy at two or more temperatures by steps, and cooling to room termperature after each step. Compare with progressuve aging   Iron An element that has an average atomic number of 55.85 and that always, in engineering practice, contains small but significant amounts of carbon. Thus iron-carbon alloys containing less than about 0.1% C may be referred to as irons. Alloys with higher carbon contents are always termed steels   Izod Test A pendulum type of single-blow impact test in which the specimen, usually notched, is fixed at one end and broken by a falling pendulum. The energy absorbed, as measured by the subsequent rise of the pendulum, is a measure of impact strength or notch toughness.   - J - Jig Saw Steel Hardened, tempered and bright polished with round edges. Carbon content .85. Ranges of sizes .039 to 393 in width and .016 to .039 in thickness.    - K - Killed Steel Steel deoxidized with a strong deoxidizing agent, such as silicon or aluminum, to reduce the oxygen content to such a level that no reaction occurs between carbon and oxygen during solidification.     << Top >>     - L - Lamination An abnormal structure resulting in a separation or weakness aligned generally parallel to the worked surface of the metal.   Leveling Flattening rolled metal sheet or strip.   Lithographic Sheet Aluminum Sheet having a superior surface on one side with respect to freedom from surface imperfections and supplied with a maximum degree of flatness, for use as a plate in offset printing. Long Terne A term applying to steel sheets that have been terne coated (Lead and Tin) by immersion in a bath of Terne Metal.   Low Carbon Steels Contain from 0.10 to 0.30% carbon and less than 0.60% manganese. (The product of Basic Oxygen, Bessemer, Open Hearth or Electric Processes.)     << Top >>   - M - Matt or Matte Finish (Steel) Not as smooth as normal mill finish. Produce by etched or mechanically roughened finishing rolls. Mechanical Properties The properties of a material that reveal its elastic and inelastic behavior where force is applied, thereby indicating its suitability for mechanical application; for example, modulus of elasticity, tensile strength, elongation, hardness, and fatigue limit.   Metallography The science concerning the constituents and structure of metals and alloys as revealed by the microscope. Mill Finish A surface finish produced on sheet and plate. Characteristic of the ground finish used on the rolls in fabrication. Modulus of Elasticity A measure of the rigidity of metal. Ratio of stress, within proportional limit, to corresponding strain. Specifically, the modulus obtained in tension or compression is Young's modulus, stretch modulus or modulus of extensibility; the modulus obtained in torsion or shear is modulus of rigidity, shear modulus or modulus of torsion; the modulus covering the ratio of the mean normal stress to the change in volume per unit volume is the bulk modulus. The tangent modulus and secant modulus are not restricted within the proportional limit; the former is the slope of the stress-strain curve at a specified point; the latter is the slope of a line from the origin to a specified point on the stress-strain curve. Also called elastic modulus and coefficient of elasticity. Modulus of Elasticity (tension) Force which would be required to stretch a substance to double its normal length, on the assumption that it would remain perfectly elastic, i.e., obey Hooke's Law throughout the twist.    << Top >>   - N - Natural Aging Spontaneous aging of a supersaturated solid solution at room temperature.   Nitriding 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.   Normalizing Heating a ferrous alloy to a suitable temperature above A3 or Acm and then cooling in still air to a temperature substantially below A1. The cooling rate usually is in the range 900 to1800 F/h (500 to 1000C/h)   << Top >>     - O - Oil Hardening A process of hardening a ferrous alloy of suitable composition by heating within or above the transformation range and quenching in oil.   Orange Peel A pebble-grain surface which develops in forming of metals having coarse grains. Orientation (crystal) Arrangement of certain crystal axes or crystal planes in a crystalline aggregate with respect to a given direction or plane. If there is any tendency for one arrangement to predominate, it is known as the preferred orientation; in the absence of any such preference, random orientation exists. Oxidation The addition of oxygen to a compound. Exposure to atmosphere sometimes results in oxidation of the exposed surface, hence a staining or discoloration. This effect is increased with temperature increase. Oxidation (1) A reaction in which there is an increase in valence resulting from a loss of electrons. (2) Chemical combination with oxygen to form an oxide. Overaging Aging under conditions of time and temperature greater than those required to obtain maximum strength. Overheating Heating a metal or alloy to such a high temperature that its properties are impaired. When the original properties cannot be restored by further heat treating, by mechanical working, or by combination of working and heat treating, the overheating is known as burning.   Oxidized Surface A surface having a thin, tightly adhering oxidized skin.   << Top >>   - P - Pass A term indicating the process of passing metal through a rolling mill. Pass (1) A single transfer of metal through a stand of rolls. (2) The open space between two grooved rolls through which metal is processed. (3) The weld metal deposited in one run along the axis of a weld.   Penetrant Inspection A method of non-destructive testing for determining the existence and extent of discontinuities that are open to the surface in the part being inspected. The indications ore made visible through the use of a dye or fluorescent chemical in the liquid employed as the inspection medium. Physical Properties Properties other than mechanical properties, that pertain to the physical nature of a material; e.g., density, electrical conductivity, thermal expansion, reflectivity, magnetic susceptibility, etc. Pickling Removing surface oxides from metals by chemical or electrochemical reaction. Pickling The process of chemically removing oxides and scale from the surface of a metal by the action of water solutions of inorganic acids.   Pipe (defect) Contraction cavity, essentially cone-like in shape, which occurs in the approximate center, at the top and reaching down into a casting; caused by the shrinkage of cast metal. Pit (defect) A sharp depresssion in the surface of the metal.   Primes Metal products, such as sheet and plate, of the highest quality and free from visible surface defects.   Progressive Aging An aging process in which the temperature of the alloy is continuously increased during the aging cycle. The temperature may be increased in steps or by any other progressive method. Compare with interrupted aging. Proof Stress (1) The stress that will cause a specified small permanent set in a material. (2) A specified stress to be applied to a member or structure to indicate its ability to withstand service loads.   << Top >>   - Q - 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 Hardening Hardening by austenitizing and then cooling at a rate such that a substantial amount of austenite is transformed to martensite.   Quench Hardening (Steel) 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.   << Top >> - R - 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. Recovery Reduction or removal of work-hardening effects, without motion of large-angle grain boundaries. Recrystallization A process whereby a distorted grain structure of cold worked metals is replaced by a new, stress-free grain structure as a result of annealing above a specific minimum temperature for a specific time.   Rockwell Hardness (Test) A standard method for measuring the hardness of metels. The hardness is expressed as a number related to the depth of residual penetration of a steel ball or diamond cone (brale) 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. Various dial readings combined with different major loads, five scales designated by letters varying from A to H; the B and C scales are most commonly in use.   Rolled In Scale A surface defect consisting of scale partially rolled into the surface of the sheet. 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.   << Top >> - S - 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. Scaling Forming a thick layer of oxidation products on metals at high temperatures. 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. 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.   Shortness A form of brittleness in metal. It is designed as cold, hot, and red, to indicate the temperature range in which the brittleness occurs. 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. 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. Slab A piece of metal, intermediate between ingot and plate, at least twice as wide as it is thick. Slag A product resulting from the action of a flux on the nonmetallic constituents of a processed ore, or on the oxidized metallic constituents that are undesirable. Usually slags consist of combinations of acid oxides with basic oxides, and neutral oxides are added to aid fusibility. Slag A nonmetallic product resulting form mutual dissolution of flux and nonmetallic impurities in smelting and refining operations. 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.   Spalling The cracking and flaking of particles out of a surface.   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. Stress Relief Low temperature annealing for removing internal stresses, such as those resulting on a metal from work hardening or quenching. 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.   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.   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.    << Top >>   - T - Tarnish Surface discoloration on a metal, usually from a thin film of oxide or sulfide.   Telescoping Transverse slipping of successive layers of a coil so that the edge of the coil is conical rather than flat.   Temper (1) In heat treatment, re-heating hardened steel or hardened steel or hardened cast iron to some temperature below the eutectoid temperature for the purpose of decreasing the hardness and increasing the toughness. The process also is sometimes applied to normalized steel. (2) In tool steels, temper is sometimes used, but inadvisedly, to denote the carbon content. (3) In nonferrous alloys and in some ferrous alloys (steels that cannot be hardened by heat treatment), the hardness and strength produced by mechanical or thermal treatment, or both, and characterized by a certain structure, mechanical properties, or reduction in area during cold working.   Tensile Strength In tensile testing, the ratio of maximum load to original cross-sectional area. Also called ultimate strength.   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.   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.   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 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. Toughness Property of resisting fracture or distortion. Usually measured by impact test, high impact values indicating high toughness. Twist A winding departure from flatness.    << Top >>   - U - Ultimate Strength The maximum conventional stress, tensile, compressive, or shear, that a material can withstand.     << Top >>       - V - Vanadium Chemical symbol V. Element No. 23 of the periodic system; atomic weight 50.95. Gray-white, hard metal, unaffected by atmospheric influences or alkalis but soluble in most strong acids; melting point 3119 (degrees) F.; boiling point about 6150 (degrees) F.; specific gravity 5.87. It cannot be electrodeposited. Its principal functions as an alloy in the making of tool steels. (1) Elevates coarsening temperature of austenite (promotes fine grain). (2) Increases hardenability (when dissolved) (3) Resists tempering and causes marked secondary hardening.   Vickers Hardness (Test) Standard method for measuring the hardness of metals, particularly those with extremely hard surfaces; the surface is subjected to a standard pressure for a standard length of time by means of a pyramid shaped diamond. The diagonal of the resulting indention is measured under a microscope and the Vickers Hardness value read from a conversion table.   << Top >>     - W - Wavy Not flat. A slight wave following the direction of rolling and beyond the standard limitation for flatness. Weldability Suitability of a metal for welding under specific conditions. Wetting A phenomenon involving a solid and a liquid in such intimate contact that the adhesive force between the two phases is greater than the cohesive force within the liquid. Thus a solid that is wetted, on being removed from the liquid bath, will have a thin continuous layer of liquid adherring to it. Foreign substances such as grease may prevent wetting. Addition agents, such as detergents, may induce wetting by lowering the surface tension of the liquid. Work Hardening Increase in resistance to deformation (i.e. in hardness) produced by cold working.   << Top >>     - X - X-Rays Light rays, excited usually by the impact of cathode rays on matter, which have wave lengths between about 10-6 cm, and 10-9 cm; also written X-rays, same as Roentgen rays.   << Top >>     - Y - Yield Point The first stress in a material less than the maximum obtainable stess at which an increase in strain occurs without an increase in stress. Also known as upper yield stress.   - Z - Zinc Chemical Symbol Zn. Element No. 30 of the periodic system; atomic weight 65.38. Blue-white metal; when pure, malleable and ductile even at ordinary temperatures; melting point 787 (degrees) F.; boiling point 1665 (degrees) F., specific gravity 7.14. Can be electrodeposited; it is extensively used as a coating for steel and sheet zinc finds many outlets, such as dry batteries, etc. Zinc-base alloys are of great importance in die casting. Its most important alloy is brass.   << Top >>