This ever-expanding glossary is your guide to the most commonly used terms and phrases in metal.
Alloy Steel - Steel containing significant quantities of alloying elements (other than carbon and the commonly accepted amounts of manganese, silicon, sulfur, and phosphorus) added to effect changes in mechanical properties by heat treatment.
Alloying Elements - Chemical elements added for changing the properties of the finished products. Check out 11 common alloying elements here.
Annealing - A process of heating and cooling applied to induce softening or to achieve a specific microstructure.
Arc Welding - Welding accomplished by using an electric arc that may be formed between a metal or carbon electrode and the metal being welded; between two separate electrodes, as in atomic hydrogen welding; or between two separate pieces being welded, as in flash welding.
Bands - The initial coil product produced by rolling a slab on a hot strip mill, generally to thickness ½’’ and lighter. It is usually further processed as follows:
1. Rerolled into cold rolled sheets.
2. Leveled and cut into plates (3/16” and over).
3. Leveled and cut into hot rolled flat sheets (lighter than 3/16”).
Billet- A solid semi-finished round or square product that has been hot worked by forging, rolling or extrusion.
Case Hardening - A process of hardening a ferrous alloy so that the surface layer of case is made substantially harder than the interior or core. Typical case-hardening processes are carburizing and quenchings, cyaniding, carbonitriding, nitriding, induction hardening and flame hardening.
Coil Breaks - Creases or ridges which appear as parallel lines, transverse to the direction of rolling. They generally extend across the width of the sheet.
Cold Drawing - The process of pulling a hot rolled bar through a die of lesser size. Cold drawing gives the hot rolled bar a bright, clean, uniform surface and increases tensile and yield strength. Cold drawing also increases torsional strength, surface hardness, wear resistance and imparts significant improvement in machinability. In some cases, cold drawn bars subsequently may be subjected to grinding and polishing operations.
Cold Rolled - Flat rolled products for which the approximate required thickness has been obtained by rolling without heating at approximate room temperature.
Corrosion Resistance - The ability of a metal to withstand attack in an environment that is conducive to chemical or electrochemical reaction.
Deep Drawing - Forming shaped articles or shells by forcing sheet metal into a die.
Deoxidizing- The removal of oxygen from molten steel by use of suitable elements that react with oxygen readily.
Ductility – The ability of a material to deform plastically without fracturing, generally measured by elongation or reduction of area in a tensile test.
Elongation- In tensile testing, the increase in gauge length, measured after fracture of the specimen, usually expressed as a percentage of the original gauge length.
Extrusion - Shaping metal into a continuous form by forcing it through a die or appropriate shape.
Fatigue - The tendency for a metal to break under conditions of repeated cyclic stressing considerably below the ultimate tensile strength.
Finish - In the steel industry, refers to the type of surface condition desired or existing in the finish product. For cut plates, finish refers to the quantity of an edge or surface required for the part to be acceptable.
Forging- Forming hot metal into the desired shape by means of hammering or pressing.
Free Machining - A term pertaining to steel which, in cutting operations, breaks into small chips, requires low power consumption, and results in superior surface finish and long tool life; these machining characteristics are imparted to steel by additives such as sulfur and/or lead.
Galvanizing - The process of applying a coating of zinc to the finished cold-reduced sheet or to fabricated parts made from strip products. The coating is applied by hot dipping or electrolytic deposition.
Galvannealed - An extra tight coat of galvanizing metal (zinc) applied to a soft steel sheet, after which the sheet is passed through an oven at about 1200 degrees Fahrenheit. The resulting coat is dull gray without spangle especially suited for subsequent painting.
Gauge - This number, which typically ranges between 3-30, indicates the thickness of a metal sheet. While the actual numbers do not indicate a specific dimensional value, the higher the gauge number the lower the thickness. Download a gauge conversion chart for more information.
Grinding and Polishing – Finishing operations that are applied to bars. First the bars are ground to close tolerance in centerless grinders and kept very straight during the operation. They are then saw cut on both ends to give a square, true cut, and burnished to a brilliant, bright finish. The results are bars with extremely close size tolerance, a high degree of straightness and a superior finish.
Hardness- Ability to resist penetration.
Hardenability- In a ferrous alloy, the property that determines the depth to which hardness can be induced by austenitizing and quenching.
High-Strength Low-Alloy Steels (HSLA) - High-strength low-alloy steel comprises a group of steels with chemical compositions specially developed to impart higher mechanical property values, and, in certain of these steels, materially greater resistance to atmospheric corrosion than is obtainable from conventional carbon structural steels.
Ingot - The solidified steel formed in a mold for subsequent rolling or forging.
Kerf - That part of the material lost through processing. The amount will vary, depending on the type and thickness of material, and the process used.
Leveling - The flattening of steel plate and sheets. There are several methods, such as roller leveling and stretcher leveling.
Machinability - This indicates the relative ease at which a piece of metal can be machined.
Merchant Quality - Bars produced for a wide range of uses, such as structural and similar miscellaneous applications, involving mild cold bending, mild hot forming, punching, and welding. On merchant quality bars, there is no limit on deoxidation practice of chemical limits beyond standard limits for carbon, manganese, phosphorus and sulfur.
Mill Edge - Normal rounded edge produced in hot rolling of flat steel. Does not conform to any specified radius.
Normalized - Condition of steel that has been heated to a suitable temperature above the transformation range and cooled in air to a temperature sustainability below the transformation range.
Pickling – Removing surface oxides from metals by chemical or electro-chemical reaction.
Quench and Temper – The steel is rapidly cooled from above its critical temperature range (austenitizing) to a temperature far below this range. Water or oil is used to accelerate the cooling. In the as-quenched condition, the product is not suitable for most commercial applications because of its poor ductility and high hardness. The steel must, therefore, be tempered in order to soften it somewhat to improve its ductility and toughness and relive internal stresses. Tempering is a reheating treatment done at temperatures usually in the range between 800 F and 1200 F.
Reduction – Reducing thickness of sheet or strip by hot or cold rolling.
Resulfurized Steels - Steels to which sulfur has been deliberately added to improve machinability.
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.” Can also be a process of coiling sheet into open cylinders.
Screw Stock - Ordinarily, free machining types of alloy, used for making screw machine products.
Sheared Edge - Used when referring to plates that have an edge produced by shearing.
Slitting - The production of narrow widths from wider sheet by means of a rotary knife or knives.
Special Quality - Bars of Special Quality are used when the end use, method of fabrication, or subsequent processing requires characteristics not available in Merchant Quality bars. Some end uses or fabrication procedures can make necessary one of more additional characteristics which may be specified as requirements.
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 electrical current is passed during a very short interval so that fusion occurs over a small area at the interface between the pieces.
Temper - A condition produced in sheet steel by mechanical, chemical or thermal treatment. A given steel may be in fully softened or annealed temper, or it may be cold worked to the hard temper, or further to spring temper. Intermediate tempers produced by cold working (rolling) are called "quarter hard," "half-hard," and "three-quarters hard," and are determined by the amount of cold reduction.
Tension Leveling - A process for improving flatness in coils by pulling in tension.
Tensile Strength- Also referred to as ultimate strength, it is the maximum conventional stress (tensile, compressive, shear) that a steel can withstand.
Tolerance – Indicates the specified limits of deviation from a dimension.
Click below to download specific tolerances by product
Torsion – Strain created in a material by a twisting action. Correspondingly, the stress within the material resisting twisting.
Turning and Polishing - The process of cold finishing hot rolled bars by machining to the desired size on a lathe or turning machine, then polishing by rotating them through hardened steel rolls.
Toughness - Ability of steel to absorb considerable energy and deform plastically before fracturing.
Ultimate Strength - This indicates the maximum conventional stress (tensile, compressive, shear) that a steel can withstand.
Wear Resistance - The ability to withstand impairment or loss of material due to rubbing or other frictional action.
Yield Strength (Yield Point) - The stress at which steel exhibits a specified deviation from proportionality of stress to strain.