Iron is a chemical element represented by the symbol "Fe" on the periodic table. This element is one of the most abundant metals in the world. It has become a preferred material in many industrial applications due to its high strength, conductivity, and castability. In nature, it is commonly found in minerals in the form of oxides, sulfides, and carbonates. Hematite and magnetite are the most common mineral forms of iron. This mineral form is converted into pure iron by various processes and used. Both in prehistoric and modern times, many technological advances and structural developments have been made thanks to the advantages provided by iron.
Iron was formed as a result of nuclear fusion reactions that took place in the cores of massive stars billions of years after the formation of the universe. When stars reach the end of their lives, they have the conditions of intense pressure and temperature under which light elements such as hydrogen and helium combine to form heavier elements. Under these extreme conditions, nuclear fusion of heavier elements such as iron takes place. However, iron is formed until it reaches a point where it does not produce energy for fusion in the cores of stars. After this stage, the star cannot produce energy and collapses under the influence of gravity. As a result, supernova explosions occur. During these explosions, many elements including iron are scattered into space. Over time, these scattered elements contribute to the formation of new stars, planets, and other celestial bodies. Earth is also a planet formed by the coming together of these elements, and therefore iron is one of the components of Earth.
The main raw material source of iron is iron minerals found in nature. These minerals represent the natural states of iron and have a variety of components. Hematite (Fe2O3) and magnetite (Fe3O4) are the most common of these minerals. In addition, other iron-bearing minerals such as limonite (FeO(OH)·nH2O) and siderite (FeCO3) are also important.
These minerals are extracted from the Earth's crust through mining activities. The resulting raw material is then subjected to metallurgical processes to purify it and obtain the iron element. In these processes, the iron mineral is ground, concentrated, and processed with different temperature and chemical treatments, thus obtaining pure iron metal and iron alloys.
The discovery and use of iron dates back to prehistoric times. It is believed that most of the first iron objects were made of meteoric iron, meaning that this iron was obtained from the meteor that fell from the sky. This type of iron was easier to process as it was found in nature as a pure metal.
However, the beginning of iron mining and metallurgy, that is, the extraction and processing of iron from the Earth's crust, dates back to the 3rd millennium BC, the beginning of ancient civilizations. Early evidence of iron mining and metallurgy has been found in regions such as Mesopotamia, Egypt, and India.
By the 12th century BC, ironworking techniques had significantly advanced, and the period known as the Iron Age began. During this period, iron became an important material in the production of weapons, tools, and building materials. Ancient civilizations such as the Hittites, Hittites, and Assyrians were particularly prominent in the production and use of iron. These developments accelerated with the realization that iron had superior properties to other metals. This period is known as the time when bronze was replaced by iron and iron became a historically important metal.
Iron is rarely found in nature in its pure metal form. Instead, it is typically found in the Earth's crust as various mineral compounds.
The most common and economically important iron minerals are oxides. The most common of these are hematite (Fe2O3) and magnetite (Fe3O4). Hematite is a reddish-brown to black mineral, and most iron mining is derived from this mineral. Magnetite is a black, magnetic mineral, and in some regions, it is the primary source of iron production.
In addition, iron sulfides include pyrite (FeS2) and pyrrhotite (Fe1-xS). Pyrite is a yellow mineral, commonly known as "fool's gold," and is not used in iron production, while pyrrhotite serves as a source for iron production in some regions.
Iron is also found in the form of the carbonate mineral siderite (FeCO3). Siderite is typically brown to greenish-gray in color.
In silicate form, iron is found as a component of minerals found in igneous and metamorphic rocks, such as olivine and garnet.
These minerals can be found in a variety of formations and deposits in the Earth's crust. Iron mining occurs in areas where these minerals are found in economically workable concentrations. These mineral deposits are often associated with ancient seabeds or magmatic activity.
Iron is a silver-gray metal with a bright metallic luster. It is a hard and tough material that is ductile and malleable under certain temperatures and conditions. Iron has excellent conductivity, meaning it conducts electricity and heat well. It is also known for its magnetic properties, especially at certain temperatures. The density of iron is about 7.87 g/cm³, making it one of the densest elements found in the Earth's crust. Chemically, iron reacts with air and moisture to oxidize, which can cause rust to form on its surface over time.
The strength, durability, and workability of iron make it an ideal material for many industrial applications. In the construction industry, iron is used to produce reinforcing bars, beams, and other structural components. This plays a critical role in the construction of buildings, bridges, and dams. In the automotive industry, iron is essential for the production of engine components, chassis, and body parts. In rail transportation, iron is a basic material for train tracks, locomotives, and cars. In addition, iron is used in agricultural equipment, shipbuilding, machinery manufacturing, and many other areas. Iron is also used as the main component in the production of various metal alloys, especially steel. Steel further expands the range of applications for iron by increasing its strength and making it more resistant to rust.
Iron has a relatively high melting point among metallic elements. This is one of the reasons why iron is preferred in structural applications, as this property makes iron resistant to high temperatures. The melting point of pure iron is 1538°C. At this temperature, iron in its solid form changes to liquid form. This property makes iron suitable for casting and shaping processes. The melting point also plays a critical role in the production of iron alloys and compounds, as at this temperature, iron can easily combine with other elements.
Iron is an element that exists as atoms in nature, and in this context, it does not have a "lifespan." However, the concept of lifespan applies to products and structures made of iron. Iron reacts with oxygen and water to oxidize. This oxidation results in the formation of a reddish-brown rust layer on the iron. This rusting can weaken the structural strength of iron and eventually lead to its deterioration.
The rate of iron rusting depends on many factors. These factors include weather conditions, the amount of moisture to which the iron is exposed, air pollution, and other substances that the iron comes into contact with. For example, the rate of iron rusting is faster in areas near salty water than in inland areas. Similarly, iron oxidizes more quickly in acidic environments.
Various protection methods are used to extend the lifespan of iron. These methods include paint coatings, galvanization, and the production of stainless steel. These measures slow down oxidation by preventing the direct contact of iron with oxygen and water.
The lifespan of iron can vary depending on the environment in which it is used, the protection methods applied to it, and the environmental conditions to which it is exposed. However, with appropriate protective measures, the lifespan of products and structures made of iron can last for hundreds of years.
Iron is a versatile material with excellent mechanical properties and workability. It is used in a wide variety of applications, including:
Iron is also a major component in the production of various alloys. Steel is the most well-known alloy of iron, and it expands the range of applications for iron by increasing its strength and reducing its corrosive properties.
In the world, iron is mined in countries such as Australia, Brazil, China, and India. In Turkey, iron mining is carried out in many regions, including Sivas, Malatya, and Erzincan.