Metal Manufacturing 140

alloy steel

Steel that contains added materials that change the property of the metal. Common alloy elements include chromium, manganese, molybdenum, and nickel.

annealing

The steady heating of a metal at a certain temperature followed by a gradual cooling process. Annealing can be done to restore ductility.

basic oxygen furnace

A type of furnace used during the steelmaking process that injects pure oxygen into a batch of pig iron and other materials to burn the contents and produce steel.

big-end down mold

A type of ingot mold that is wider at the base and narrower at the top. This shape makes it easier to remove the ingot once it cools.

billet

A small, semi-finished piece of metal that is rectangular, circular, or square in shape. Billets are smaller than blooms.

blast furnace

A tall furnace built with steel and brick that is used to produce pig iron from the original iron ore.

bloom

A semi-finished piece of metal that is rectangular or square in shape. Blooms are larger than billets.

carburizing

A surface hardening method that heats a metal within a carbon-rich environment to increase carbon levels on the metal surface.

cast

To pour a molten metal into a mold.

charge

The mix of material that is placed in a furnace.

coke

A carbon-based fuel used to heat the contents of a blast furnace.

cold drawing

A cold-working process that pulls a piece of metal through a smaller opening to compress and lengthen the metal. Cold drawing removes the scale that develops from hot working and creates accurate stock sizes.

cold rolling

A cold-working squeezing process that passes a flat piece of metal between two rolls to flatten and lengthen the metal.

cold working

The shaping of metal at temperatures much lower than the metal's molten state. Steel is often cold worked at room temperature.

continuous casting

The process of pouring molten metal into a mold that creates a long, continuous slab of metal, which is then separated into pieces at the end of the casting process.

die

A component with specific dimensions used to shape metal that is forced through or against it.

ductility

The ability of a metal to be drawn, stretched, or formed without breaking.

electric arc furnace

A type of furnace used during the steelmaking process that shoots electric arcs between electrodes to burn a combination of pig iron and other materials to produce steel.

electrical arc

A strong and sudden bolt of electricity.

hot rolling

A process that passes metal heated at elevated temperatures between two rolls to flatten and lengthen the metal. Hot rolling leaves a tough scale on the metal.

hot working

The shaping of metal at temperatures close to the metal's molten state. Steel is typically hot worked at temperatures approximately 1300°F (700°C).

impurities

An unwanted substance that reduces the quality of a material.

ingot

The first solidified piece of steel from which other parts are made.

ingot casting

The process of pouring molten metal into separate molds until the metal solidifies into ingots.

ingot mold

A container in which molten steel is poured that is designed to hold the steel until it solidifies.

iron ore

The natural form of iron, which is a combination of iron metal with other minerals and rocks.

limestone

A sedimentary rock that is used in blast furnaces to remove impurities from iron ore.

machinability

The ability of a metal to be shaped by machine processes such as milling, grinding, turning, or drilling.

manufacturing

The process of producing and shaping a product on a large scale, often through the use of large machinery.

molten

A metal in its liquid state.

pickling

The soaking of metal in an acid to remove the hardened scale that develops from hot working. Steel is often pickled before it is cold worked.

pig iron

The processed iron that is poured from a blast furnace. Pig iron still contains impurities.

raw material

An unprocessed material that has not been manufactured.

slab

a flat, semi-finished piece of metal that is at least twice as wide as it is thick.

slag

The rock-like waste that separates from pig iron and is removed from a blast furnace.

solidify

To change from a liquid to a solid.

stainless steel

An alloy steel that is designed to resist corrosion.

steel

A metal consisting of iron and carbon, usually with small amounts of manganese, phosphorus, sulfur, and silicon as well.

steelmaking process

The process used to make steel from pig iron and other materials.

stock

The raw material from which products are made through manufacturing.

strand casting

Another term for continuous casting.

tolerance

The unwanted but acceptable deviation from the desired dimension. Accurate dimensions require tighter tolerances.

tool steel

A type of steel designed with high wear resistance, toughness, and strength. Tool steels are used to make cutting tools, dies, and fixtures.

tundish

The device located at the top of a continuous caster that regulates the flow of molten steel.