Alloying Element- An element added to a metal to effect changes in properties and which remains within the metal.

Annealing-A process of heating and cooling steel sheets, bars, rods, etc. to remove contained stresses, or to alter mechanical or physical properties.

Bar Mill-A rolling mill equipped with grooved rolls to produce from reheated billets an elongated steel product of round, square or other cross section.

Billet-A solid semi-finished round or square product that has been cast or hot worked by rolling.

Billet Mill-A rolling mill for converting blooms that have been heated to rolling temperatures into billets to be used in the production of wire rod, bars and seamless pipe. The billet may be square, rectangular or round in section, the width not exceeding twice the thickness. The cross - sectional area is usually not more than 36 square inches.

Blast Furnace-A vertical shaft furnace, equipped with a hot air blast, for producing pig iron from iron ore. The furnace is operated on a continuous basis.

Bloom-A semi-finished product, rectangular in cross section, produced on a continuous caster. See also billet. For steel, the width of a bloom is not more than twice the thickness, and the cross-sectional area is usually not less than about 230 cm² (36 in²).

Basic Oxygen Furnace-A large rotatable vessel sometimes called a "converter" or "decarburizing furnace" used to make steel by refining pig iron.

Coke Ovens-Large ovens for heating coal in the absence of air to drive off volatile matter and leave carbon-rich coke as the solid residue. The process results in the production of metallurgical coke and coke breeze, as well as by-products such as tar, gas and aromatic hydrocarbons.

Cold Reduction Mill-A mill for rolling sheet and strip at approximately room temperature with the object of reducing its thickness. Cold reduction develops higher tensile properties, greater surface hardness, better finish and closer dimensional tolerances in the product.

Conditioning-The removal of surface defects from semi-finished steel by chipping, scarfing, grinding or machining to prepare it for further processing.

Continuous Casting-A process for casting molten steel directly into semi-finished shape (e.g. bloom, billet or slab).

Continuous Galvanizing-The process of coating a continuous strip of steel with zinc by running it through a bath of molten zinc.

Controlled Rolling-A hot rolling process in which the temperature of the steel is closely controlled, particularly during the final rolling passes, to produce a fine-grain microstructure.

Flat Rolled Products-Plate, sheet and strip products of rolling mills equipped with smooth-faced rolls in contrast to grooved or cut rolls used in the manufacture of shapes (e.g. bar).

Flux-Materials (e.g. limestone or dolomite) used in iron and steelmaking furnaces to combine with impurities in the charge and produce a molten slag, which can be separated from the metallic end product. (see limestone)

Formability-The relative ease with which a metal can be shaped through plastic deformation.

Galvanizing-The process of coating steel with zinc by immersing it in a bath of molten zinc.

Galvannealing-The process of coating steel with a zinc-iron alloy by immersing it in a bath of molten zinc followed by heating of the strip.

Hot Strip Mill-A mill for rolling heated steel slabs through a series of rolling stands to produce sheet steel in coil form.

Limestone-(see flux) The most common flux, called calcium carbonate (CaCO₃) or more commonly "stone". Used as a flux in the Blast Furnace with dolomite ((Ca,Mg)CO₃). Limestone also has endothermic properties (soaks up heat) and is charged to the BOF vessel as an effective coolant.

Oxygen Lance-A water-cooled steel lance having a copper tip with three 1.3in diameter holes, lowered into the BOF vessels for decarburization of the hot metal. Oxygen is blasted through this lance at a very high velocity (mach 2.3 or 1700 mph), a high flow rate (13000 cfm), and therefore large quantity (1/2 a ton per minute). Cooling water flow rates are 900 gallons per minute.

Pickling-The process of chemically removing scale, oxide and other foreign material from steel to obtain a chemically clean surface. Hydrochloric acid is the cleaning agent generally employed.

Pig Iron-The direct metallic product, either solid or molten, of a blast furnace smelting iron ore.

Refractories-Materials used for furnace linings which do not melt at furnace temperatures. They also possess a relatively high degree of resistance to the destructive influences of abrasion, thermal shock, pressure, corrosion and erosion.

Rolling Mill-A rolling mill generally consisting of four horizontal rolls mounted one above the other, revolving at the same speed, but in opposite directions so that the steel to be processed is passed between them. The operation forms the steel into the desired shape and improves its mechanical characteristics. Rolling mills may comprise a series of rolling stands and may be classified by purpose (e.g. Hot Strip Mill) or by design (e.g. four-stand).

Roughing Mill-A rolling mill used for preliminary or initial rolling to shape steel and remove surface scale.

Scale-An oxide of iron formed on steel during hot working or upon exposure to air or steam at elevated temperatures. The scale is normally removed during processing to improve the quality of the final product.

Sintering-A process of fusing fine iron ore and iron-bearing materials, such as mill scale, with fluxes by applying heat on a moving grate, so that the product (sinter) may be charged into a blast furnace without impeding the upward flow of heated gases.

Slab-A semi-finished hot rolled product continuously cast and intended for further rolling into strip or other flat products.

Steel-A malleable alloy of iron and carbon produced by melting and refining pig iron and/or scrap steel. Carbon (in a range from 0.002% to 1.7%) is an essential ingredient but other elements, such as manganese and silicon, may be included to provide specific properties.

Strand Casting-A generic term describing continuous casting of one or more elongated shapes such as billets, blooms or slabs; if two or more strands are cast simultaneously, they are often of identical cross section.

Temper Mill-A mill for cold rolling steel sheet or strip to produce desired surface finish, flatness and mechanical properties.

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

Vertical Edger-A vertical rolling unit on a rolling mill for shaping the edges of the product.