There are different recycled materials in the world and serves as a component for some products like home appliances, industrial machinery, cars, and construction material. A good number of these components are metals which are used in the manufacturing of several products. We have two types of metals: ferrous and non-ferrous metals. For the benefit of this post, the focus is on ferrous alloys only.
You’d get insights on ferrous metals and the reasons why it’s a useful element in the production process of manufacturing companies. The common forms of ferrous metals would be highlighted with details of their unique components. Furthermore, its peculiar properties in its different would be identified as well.
Definition of ferrous metal
Ferrous metals are elements with iron and magnetic properties which offer little contention to rust. Most ferrous metals are good conductors of electricity which makes it a suitable element in the manufacture of electronics. The metals are durable and possess malleable strength like cast iron and steel. The metal can be extracted from iron ore in the earth’s crust which contains compounds like iron oxide.
Ferrous metals are mainly composed of iron, and they are used in the manufacturing of commercial and domestic tools, shipping containers, industrial pipes, construction, rails, tools, nuts and bolts, machinery, aircraft, drills, and electrical appliances. Iron and steel remain the most common forms of ferrous metals.
Ferrous metals include the following:
- Alloy steel
- Carbon steel
- Cast iron
- Wrought iron.
The features of carbon and alloy steel
Steel is a ferrous metal, and about 40% of steel production in the world is made from scrap because it’s cheaper to make use of recycled steel rather than to produce new steel through the mining process. Furthermore, recycling steel gulps less energy in comparison to forming steel from raw materials. The physical properties of steel aren’t lost during the recycling process so it can be used again. About 500 million tons of steel is formed from scrap materials and manufactured using different melting furnaces like electric-arc, induction, open-hearth, crucible, and Bessemer converter.
Carbon steel: These are ferrous metals that are made of iron with carbon elements, and produced in open-hearth furnaces. Carbon steels are alloyed with other elements like chromium and nickel to enhance its physical properties. It can be welded, forged, or machined for the production of chisels, nails, gears, hammer, fenders, and rivets.
Alloy steel: The ferrous metal has higher durability than carbon steel, and it’s used in the manufacturing of different equipment. The metal is melted in the induction and electric-arc furnace with mixtures of limestone, scrap, iron ore, and pig iron. Common elements used in alloy steel are molybdenum, chromium, nickel, silicon, tungsten, and vanadium. Nickel helps to increase the strength and toughness of the steel even as it reduces the temperature for hardening. Chromium is used to prevent corrosion and improve the resistance of shock. Chromium preserves metals from rust because it enables the top molecules of the metal to oxidize and still stay bonded to the metal below through the process of passivation thereby forming an impenetrable shell.
The features of Wrought and Cast iron
Wrought iron: This is a ferrous metal produced in a puddling furnace and made from pig iron. The presence of slag makes it resistible to oxidation and corrosion responsible for rusts. Wrought iron is useful for nails, chains, fencing, barbed wire, decorations, ornaments, and porch railings. The advantage of wrought iron is due to its ability to quickly bend when heated or cold, and the rate of rusting is low. However, its low level of hardness is a limitation, and it melts gently without emitting sparks.
Cast Iron: This is a ferrous metal that has low melting temperature, and it’s similar to carbon steel. However, the difference lies in the fact that it has silicon with additional carbon content within the range of 4.5 percent while the range for basic steel is between 0.03 and 1.7 percent. It reacts slowly with molding materials but doesn’t have sufficient malleability to be forged. It is produced by mixing pig iron, limestone, scrap metal, and carbon, then heating them up till a suitable level of all the elements is attained. Cast iron enables the production of complex shapes, and it has excellent fluidity which is desirable for casting. It’s also brittle and robust with lubricating properties.
Ferrous metals have magnetic properties and a high amount of carbon, so they are susceptible to rust when laid bare to the elements such as moisture and acidic environment. However, wrought iron is preserved due to its purity and stainless steel because of the presence of chromium. They also have tensile strength, hardness, and durability. Carbon steel has less ductility and toughness,
Recycling of ferrous metals
A lot of companies make use of scrap ferrous metals as it’s more cost-effective with less environmental hazards because it reduces air pollution and utilization of water. Another benefit of recycling ferrous metals is the reduction of solid waste deposits in landfills which is quite expensive. Some ferrous metals can be recycled such as cars, vans, home appliances, railway tracks and it saves iron ore, limestone, and coal. Since the metals are magnetic, the scraps could be retrieved with the use of a magnet and transferred to the recycling unit.
The process of recycling ferrous scrap metals is cheaper than producing metal directly from iron ore. The most significant source of scrap ferrous metals is the processing of old automobile by crushing and flattening the body before shredding into little pieces. Afterward, the remelting and recasting of the scraps is the next step in the recycling procedure. However, one disadvantage of ferrous metal scraps is increasing the technical challenge in production due to the introduction of impurities into the steel.
Many companies use ferrous metals because they are essential in the production of a wide range of tools, machineries, household appliances and equipment. Ferrous metals can be derived from iron ore or through the recycling of scraps as a cheaper alternative. There are different forms of ferrous metals with their peculiar features and characteristics.
It is necessary to apply caution when extracting scraps for recycling to limit technical difficulties and the impurities in the production process.
Also, ensure you understand the characteristic of the ferrous metal before adopting its use for any specific purpose.
Would you prefer to extract ferrous metals from iron ore or simply resort to metal scraps?