Cast iron is normally used in the manufacture of heavy crushing machinery, machine tool parts, brake drums, car cylinder blocks, machine handles, gear wheels, plumbing material, as well as several household items.
Did You Know?
The amount of ferrous scrap processed daily in the US alone, is equivalent to that required for building 25 Eiffel Towers!
Chemical elements are broadly classified into two major groups-metals and non-metals. Metals are further divided into two main groups:
(1) Ferrous Metals
(2) Non-ferrous metals
The term ‘ferrous’ comes from the Latin word ferrum, meaning ‘containing iron’. These metals are generally magnetic in nature and have a high tensile strength. Iron and steel in all forms are viewed as ferrous metals, while metals that don’t constitute an iron component in them are termed as non-ferrous.
Ferrous metals may contain small amounts of other elements such as carbon or nickel, that are added (in a specific proportion) to achieve the desired properties.
These metals are present almost everywhere, be it the Eiffel tower or the intricately carved metal gates. Almost all are widely employed in the manufacturing of products like beams, machine parts, cookware, gadgets, etc.
List of Ferrous Metals
Carbon Steel
Carbon steel is a ferrous alloy with 0.05 to 2.0% carbon, and is known for its high tensile strength. It can be hardened to heat treatment, and is fairly ductile. Depending on the carbon content, carbon steel has been classified into three broad types. As the carbon content increases, the strength increases, but the ductility reduces. However, carbon steel is susceptible to rusting.
► Low-carbon Steel
▪ Also known as mild steel, it is the most commonly used ferrous metal.
▪ It Contains about 0.05 to 0.30% carbon and the rest is iron.
▪ It is malleable and ductile, and bends easily.
▪ It is used in the manufacture of nuts, screws, bolts, girders and other general metal products.
► Medium-carbon Steel
▪ It contains about 0.30 to 0.60% carbon.
▪ It is relatively harder and less ductile than low-carbon steel.
▪ It is used in the manufacture of car components like axles, gears and crankshafts.
► High-carbon Steel
▪ It contains 0.60 to 0.99% carbon, and may also contain small amounts of manganese, silicon, and copper.
▪ It is the strongest and hardest of all carbon steels.
▪ It is used to make blades, springs, and high-strength wires.
► Tool Steel
▪ Also known as tool and die steel, it is specifically used for making machine parts, metal cutting tools and dies, as well as molds used for injection molding.
▪ It contains 0.7 to 1.5% carbon, as well as molybdenum, tungsten, vanadium, and other metals.
▪ It is resistant to heat, abrasion, and corrosion, unlike other carbon steels.
Stainless Steel
▪ Also known as corrosion-resistant steel, it is an alloy of iron, nickel, and chromium.
▪ The important property of stainless steel is its high resistance to corrosion owing to the presence of chromium.
▪ It is tough and resistant to stains, hence, called stainless steel.
▪ This steel can be welded, machined and shaped easily depending on the type of steel.
▪ It is commonly used in kitchen cutlery and cookware, axles, desks, nails, medical instruments, kitchen draining boards, pipes, etc.
Cast Iron
▪ It is strong but brittle, and has a high compressive strength.
▪ It is resistant to oxidation and corrosion.
▪ It can be classified into different varieties like gray cast iron, white cast iron, malleable cast iron, and ductile cast iron.
▪ Cast iron can be bronze-welded or arc-welded, and hardened or machined.
Wrought Iron
▪ Wrought iron has a very low carbon content of 0.10 to 0.25%.
▪ It is strong and tough, yet fibrous and ductile.
▪ It is no longer produced commercially, and has been replaced by mild steel.
▪ It was used to make ornamental gates, farm and garden equipment, railings, nails, wires, etc.
Characteristics of Metals
► Are malleable (can be shaped through hammering).
► Are ductile (can be drawn into wires).
► Have high tensile strength.
► Are good conductors of heat and electricity.
► Have a lustrous appearance.
► Have high melting points.
